ColIn’s caterpillar cake


It’s my birthday and I’ll bake if I want to. The Great British Bake Off has begun! The first week was, as usual, cake week. The showstopper challenge was to create a birthday cake you wish you had as a child. If you are from the UK or are aware of Marks & Spencer, you will know about the institution that is Colin the Caterpillar Cake. A chocolate Swiss roll with a fun caterpillar shape. Everybody had one at some point (cause it’s posh, ya know!) and I wanted to pay homage to my edible insect namesake.

The recipe has been designed by Andrew from Andrew in the Kitchen, and works beautifully. Vegan alternative in the works.



4 eggs

100g caster sugar (finely granulated)

80g self raising flour (or plain flour with 1 tsp baking powder)

20g cocoa powder

Butterceam filling

100g butter

200g icing sugar

50g melted dark chocolate (72%+)


200g melted dark chocolate

1 tbsp olive oil

cooKie face

click here for the recipe for chocolate cookies


Crack open all 4 eggs into a bowl, and whisk on high until they double in size. You are making a meringue style thickness, it will be ready when your beaters make trails in the mix.

Once you’ve whipped your eggs to the desired thickness, spoon in the sugar- spoonful at a time- whisking continuously while you add.

Sieve in the flour gradually with a spoon (metal preferred). Try to mix this in as slowly as possible to not knock the air out. The least amount of stirring the better- so add the flour in little bit at a time till you get a good technique. Add the cocoa powder in the same way.

Line a 9”x13” (23cmx33cm) Swiss roll tin with parchment, make sure to have some up the sides to make it easier to take out. Pour your mixture carefully into the tin, and bake for 10-15 minutes at 350F/185c until the sponge bounces back slightly to the touch. Take out and put straight onto a cooling rack. But not for long.

Take a clean tea towel, dust with cocoa powder, and then flip your sponge onto it (parchment side up). Peel off the parchment, and before it has cooled completely, roll the sponge up tightly in the tea towel. Starting from the short end, roll it starting by folding 1 inch from the top, and then tightly roll it all the way down. Make sure it stays put in the roll, and put it into the fridge to cool completely through.

While the sponge is cooling, make the buttercream. Melt the dark chocolate, either in the microwave in 10 second bursts stirring in between, till it’s runny.

Or if your doing all the melted chocolate in one go, make a double boiler by placing a heat proof bowl over a pan of boiling water. Make sure the bottom of the bowl isn’t IN the water, and add your chocolate. To make it melt easier break the chocolate into squares first, then stir the chocolate till it has melted.

Take soft butter (room temperature) and Pour 50g of melted chocolate on top. Mix this together till it’s smooth, then add your icing sugar. Mix until combined. The darkness of the buttercream will vary depending on your amount of chocolate. Add cocoa powder if you wish to make it darker and richer in flavour.

Take your Swiss Roll out of the fridge, and gently unroll it from the tea-towel. Spread on your buttercream, thickness is up to you, it will all pour out when you roll it if there is too much anyway (as I learned).

Now roll up the Swiss Roll with the filling inside, try to get at least one swirl in the middle. If your Swiss roll has cracked in any way, or splits, be gentle, you can cover this with the melted chocolate after. Cut off the ends by about 1cm to make them look neat.

If you haven’t melted the rest of the chocolate, melt it now. Add 1 tbsp of olive oil, this will thin out the chocolate and make it a smoother pour. Thank you She Who Bakes for that tip.

Put into a jug and pour all over, evenly. For a fun effect make stripes of chocolate, and layer them up for a more textured caterpillar body.

If you are just making a Swiss roll, you are done! Success. If you are making a caterpillar cake, then make a big cookie for the face, and 3 smaller round cookies for the feet.

Take 100g icing sugar add small amount of water, gradually, until it becomes slightly runny. Put into a piping bag with a small part of the end snipped off. You will be using this to draw the face on your cookie for the caterpillar. You can also make little feet on the other cookies for the feet.

Draw a face on the big cookie, then cut the 3 smaller cookies in half. Decorate how you wish.

Affix the face and the feet using leftover buttercream. You can draw extra stripes with any leftover white icing in the piping bag, or stick sweets to the sides and top of the caterpillar. Wherever the creativity takes you.

Chill the caterpillar for 30 minutes to make it easier to cut, and you are done! Ta da!

There will be a video coming out soon with all these steps (including the cookies), but feel free to email me if you have any questions- or comment below!

See you soon

Colin x