Regular listeners might remember, back in October (2016), my oven died a week before my daughter’s birthday, which ended up resulting in a six-month wait for an entirely new kitchen. I promised to make her a birthday cake when the new kitchen was installed, and the request was put in for a rainbow cake. A few glitches here and there, meant that I only got around to it a couple of weeks ago.
This is not that cake. That cake I didn’t photograph. That cake was just for her, and consumed at all times of the day and night, including breakfast, until she waved the white flag in defeat. The idea for this cake came out of that cake.
It also gives me an opportunity to have a bit of a rant over a pet peeve of mine, namely food colouring. Yes, in a post about rainbow cake, I’m going to complain about food colouring.
Regular viewers might remember previous rants including making-stuff-look-like-stuff-it-isn’t, featuring the infamous Come Dine With Me chocolate shoe incident. A few weeks ago, I revealed my dislike of over-the-top recipes. Rainbow cakes are now part of the Things-Which-Induce-Much-Gnashing-And-Grinding-Of-Teeth.
The usual way to make a rainbow cake involves seven layers of luridly-coloured sponge cake, interspersed with dollops of unnaturally-white buttercream. Then the whole is smothered with more highly-coloured sweets or fondant or buttercream, etc, etc. Sometimes the brightly-coloured sponge is mixed together in blobs, but in general the format is pretty standard, and it all involves So. Much. Food. Colouring.
But none of this is a patch on the über villain when it comes to coloured cakes, the Red Velvet Cake.
What originally started out as a reddish hue from a reaction between the cocoa and the vinegar/buttermilk has, in the 21st century, turned into a virulent-red chocolate cake dyed with food colouring. Bottles of the stuff. Modern, concentrated gel colours mean that not as much, by volume, is required, but still. It’s a chocolate cake, people. And it’s red. Bright red. Think about that. Enough colouring to turn a chocolate cake red.
And with both red velvet and rainbow cakes, the cake itself doesn’t strike me as being particularly nice, quite apart from the American penchant for making them up using *Matilda Response* box mixes.
I wanted to see if it was possible to make a rainbow cake using the bare minimum of food colouring, that actually tasted nice, and so here we are.
The answer lies in the classic Joconde Imprime, which you may well remember from the Great British Bake Off Season 2 and my Chocolate & Orange Mousse Cake and the miniature Strawberry & Rhubarb cheesecakes from my Finale showstopper: A coloured, pound-cake paste is used to draw a design onto baking parchment, then frozen. A light, almond sponge mixture is then poured over and smoothed out, before baking in a hot oven for 5-7 minutes. When the cake is turned out, the pattern is visible on the underside of the sheets, which can then be used to make entremet-style desserts. ‘Course, back then, an orange squiggle or a red stripe was considered pretty cutting edge. Nowadays it looks tame.
Usually, the Joconde paste is piped into the desired pattern, but once cooked it can make for a rather clunky contrast with the sponge (pound cake mix vs light, airy Joconde). One solution would be to use a teeny, tiny piping tip but then it takes sooooooo looooooong to fill the parchment with a design.
I mixed a small batch of the joconde paste and divided it into seven, colouring each portion with food-gel colouring and white powder colour. I painted rainbow stripes on one parchment sheet, and two designs for the top of the cake on the other sheet. You could pipe the paste, but the thickness of the colour paste when painted on was extremely thin, leaving most of the vanilla sponge uncoloured and delicious as can be seen below. All the colour, with none of the bulk.
The inside of the cake can be whatever you like. This one is filled with two layers of strawberries in a cream-cheese cream, with the offcuts from the sponge being fitted together, jigsaw-style, to make a middle layer. Alternatively, you could make it a mousse or cheesecake or Eton Mess or buttercream – the possibilities are endless – although something that will ‘set’ will help the stability of the cake once it is removed from the mould.
You can make the rainbow pattern any design you like, however the stripes are very easy to match up, which helps to hide the join – see below. This 19cm diameter cake needed a strip of sponge almost 70cm long to form the sides – impossible to bake in a single strip.
A few more tips:
- You can make the sponge any flavour, but I got by far the best results (in terms of colour) from vanilla.
- Chocolate joconde makes the colours very muted and the blue/indigo/violet were almost indistinguishable. Avoid.
- Mixing in some white food colouring (powder) to the Joconde paste made the colours much stronger once cooked. Before baking, they are pale and more pastel in hue. Have faith!
- Make sure the decor paste covers the parchment entirely. Early experiments piping the colours and leaving gaps between resulted in large air pockets forming and spoiling the finished pattern.
- You can get an almost invisible join between the sides and the disc of sponge used for the top if you make sure your filling is almost to the rim and you mitre the edges of the sponges.
- The vanilla cream decoration was piped through a piping bag striped with neat gel colouring.
- Depending on the complexity of your design, you might want to spend time on it a day or two before you need your cake – once complete, it can stay in the freezer until needed.
Joconde décor paste
50g unsalted butter, softened
50g icing sugar
50g egg whites
60g plain flour
rainbow food colours
white food colouring powder
2tbs melted, clarified butter
- Line two 45cm x 30cm (half sheet) baking trays with baking parchment and brush thoroughly with the melted butter. Clarified butter contains no milk solids that might scorch and spoil the colours of the design. Alternatives are cocoa butter or coconut butter.
- Cream the butter and sugar until light and fluffy then gradually add the egg whites, beating continuously.
- Fold in the sifted flour.
- Divide into seven small bowls, 30g in each bowl.
- Mix in the food colouring to each bowl until the desired shade is achieved. I also added about half a teaspoon of white colouring.
- Paint your designs for the sides and top of the cake onto the two sheets of buttered parchment.
- When finished, put into the freezer until required.
180g egg whites, at room temperature
25g granulated sugar
225g ground almonds
225g icing sugar, sifted
6 large eggs
2tsp vanilla extract
80g plain flour
85g clarified butter, melted
- Preheat the oven to 220°C, 200°C Fan
- Whisk the egg whites until they form soft peaks.
- Add the granulated sugar and continue whisking until stiff peaks are formed.
- Scrape the meringue mixture into a bowl and cover with cling film to prevent the meringue collapsing, or if you have two mixer bowls, just swap over a clean one.
- Beat the almonds, icing sugar, vanilla and eggs in the bowl for 5 minutes until the mixture is light and fluffy.
- Turn the speed down to low and mix in the flour.
- Gently fold in the meringue mixture using a large spatula.
- Put the melted butter in a small bowl and mix in a cupful of the sponge batter. Pour this back into the mixing bowl and gently fold into the rest of batter.
- Retrieve your Joconde paste designs from the freezer and lay them into your baking trays.
- Divide the mixture evenly between the tins and smooth over. Pay special attention to the corners, where it is easy to accidentally leave the batter a little on the thin side.
- Bake for 5-7 minutes, until the sponges are cooked and springy to the touch and have shrunk away from the edges of the pan.
- Turn out by laying a tea towel onto a sheet of parchment, then flip the baking tray over onto the cloth. Peel off the paper to reveal the pattern, and lay it lightly on top of the sponge. Leave to cool.
- When cooled, cut strips of sponge to line the sides of the cake tin, ensuring the pattern is facing outwards against the sides of the tin. Cut a circle of sponge to line the base and lay it patterned-side down, in the bottom of the tin. Cut a second circle to make the top of the cake and set aside.
- Fill with the filling of your choice. Use the sponge cake offcuts to make a middle layer of cake if liked.
- Trim the edges of the sponge ‘lid’ and the sponge sides and join together.
- Lay a chopping board on the top of the cake to press it lightly and chill for an hour or two to firm up.
- Remove from the tin and transfer to your serving plate.
- Garnish as liked.
 No not that one. The one from the Hillaire Belloc poem: (Matilda told such Dreadful Lies) It made one Gasp and Stretch one’s Eyes!
The recipe I have for you this week is more a set of guidelines that can be adapted to whatever takes your fancy or whatever you have to hand in the cupboards.
These individual cakes were inspired by a picture I saw of a Swiss cake, the Zuger Kirchetorte, which looked delightfully neat and elegant, as one might expect of the Swiss. I tried several recipes, but became increasingly frustrated by my own ham-fistedness in reproducing the elegance: the sponge was too thick, or the meringue too thin, or too soft or too fragile. In addition, it had a LOT of alcohol in it, which is nice for a special occasion but a bit much during daylight hours.
So I abandoned that idea for something smaller, which owes its composition to the Zuger Kirchetorte, but is also much more adaptable: you can dress it up or down, depending on whatever is to hand, even improvise with ready-made components if time or patience is short.
Essentially, these individually-sized cakes are sandwiches, with a dacquoise (hazelnut meringue) as the ‘bread’ and sponge cake as the ‘filling’, all stuck together and decorated with the sandwich ‘glue’ of your choice. The look substantial, but are very light to eat.
The possibilities for variation are endless:
- Meringue: I’ve used a hazelnut dacquoise but you could swap those out for pistachios, almonds, walnuts, cashews, macadamia nuts. You could even use plain meringue, or meringue shells from the supermarket. Alongside this, you can choose to flavour the meringues by adding in freeze-dried fruit powder to complement your other ingredients.
- Sponge: literally any sponge will do, plain vanilla, rich madeira, moist almond, fatless, genoise, joconde, flavoured however you like.
- Syrup: to make your sponge luscious and tender, you can soak it in a syrup of some kind. If you don’t want to have too many flavours, then a simple sugar syrup of half sugar, half water is fine. Or you can add flavouring to the syrup such as coffee, tea infusions, fruit juices, spirits such as Kirch, Maraschino, Disaronno, mead, madeira, rum, brandy, etc.
- Filling: I’ve used a dark chocolate ganache, to be honest, because I had some in the fridge left over from something else, but milk, white and caramelised are all good choices too, as are all flavours of buttercream. For simplicity, you can also use chocolate hazelnut spread, peanut butter (smooth or crunchy), spekuloos spread, even thick, smooth jams or fruit spreads.
- Garnish: for the outsides of the cake, something that will stick on easily and match your other flavour choices. I chose nibbed and toasted hazelnuts, because I used them in the dacquoise, but you could use flaked or slivered nuts, feuilletine, crumbled biscuits, freeze-dried fruit, chocolate sprinkles, meringue crumbs, chocolate shards.
I used baking rings made from small tinned food tins (5cm diameter tins from mushy peas, in case you’re wondering) opened at both ends, but these quantities will also make one large, 24cm cake if you prefer.
Dacquoise Sandwich Cakes
Makes 8 individual sandwiches or 1 large 24cm cake.
For the Sponge
You can choose your own favourite sponge recipe if preferred. This fatless sponge recipe also happens to be gluten-free.
2 large eggs
60 g of caster sugar
a pinch of salt
1 tbsp hot water
50 g Green & Black’s cocoa
30 g of cornflour
- Preheat the oven to 180°C, 160°C Fan.
- Grease and line your tin(s) with baking parchment. Butter the parchment.
- Sift the cocoa and cornflour together.
- Whisk the eggs, sugar, water and salt together over a saucepan of hot water for 3-4 minutes, until light and frothy.
- Remove from the heat and whisk until billowy and increased in volume (about 5 minutes).
- Gradually fold in half the cocoa and cornflour, then add the remainder and fold in.
- Transfer to your tin(s), filling each about half-way.
- Bake for 10-15 minutes (20-25 minutes for a large cake) until firm and springy and slightly shrunk from the sides.
- Cool on a wire rack.
For the Dacquoise
You can grind the hazelnuts finer, but I like the texture the slightly larger pieces give.
2 large eggwhites (80ml)
2 tbsp caster sugar
2 tbsp icing sugar
1 tbs cornflour
60 g chopped, toasted hazelnuts
- Turn the oven to 120°C, 100°C Fan.
- Draw 16 circles using your baking rings as a guide onto a sheet of parchment, 2 for each sandwich.
- Turn the paper over and lay onto a baking sheet.
- Whisk the egg-whites to soft peaks, then sprinkle in the caster sugar and whisk until the meringue is firm and glossy.
- Sift the icing sugar and cornflour together and fold into the meringue.
- Sprinkle in the nuts and briefly mix.
- Spoon the dacquoise onto the prepared baking parchment and spread into the marked circles. Make sure it at least reaches the edges of the circles. It doesn’t have to be too accurate, as they can be trimmed after baking. Smooth over.
- Bake for 1 hour.
- Switch off the oven and allow the meringues to cool in the oven for 15 minutes, then prop the oven door open and allow to cool completely.
- When cold, remove from the parchment and store in a ziplock bag until required.
For the Ganache
300g plain dark chocolate
150ml double cream
- Chop the chocolate into small pieces.
- Pour the cream into a small pan and bring to a boil.
- Pour the hot cream over the chocolate and set aside for 5 minutes.
- Stir gently with a whisk until the chocolate is fully melted and the ganache smooth and glossy.
For the syrup
50g caster sugar
flavouring to suit
- Put the sugar and water into a small pan and stir over low heat until sugar is dissolved.
- Add any flavouring to taste.
- Select the eight meringues with the smoothest bases and set aside. These will be used for the top of the sandwiches, for a neat finish.
- Put the remaining meringues on a tray and spoon over a layer of ganache.
- Trim the cakes level and set onto the ganache.
- Soak with the sugar syrup. It’s almost impossible to use too little. You can see from the photograph the syrup I used only soaked a little way into the sponge, so more is better.
- Add a second layer of ganache.
- Add the remaining meringues, turning them upside down, so that the smooth bases are uppermost.
- Sprinkle your decor into a tray.
- Spread the remaining ganache in a smooth layer around the sides of the sandwiches then roll in your chosen decoration. Set aside. If you’ve made one large cake, then hold your cake on one hand and lift up handfuls of your decoration and press into the sides.
- When all the sandwiches are coated, transfer to a dish and cover with clingfilm. This will keep the meringues from absorbing too much moisture.
- Chill in the fridge for at least 3 hours to firm up.
- When ready to serve, dust the tops liberally with icing sugar and use a hot skewer to caramelise the sugar in an abstract design.