I've tried and tested the best caterpillar cakes for your kid's birthday party - and you won't believe the favourite (hint: it's not Colin)

Wondering which supermarket sells the best caterpillar cake for your little ones' birthday party? I've taste tested them all...

Supermarket caterpillar cakes lined up on a table decorated for a kids birthday party
(Image credit: Future/Jessica Ransom)

Forget Cuthbert versus Colin, I've tried and tasted caterpillar cakes from not only Aldi and M&S but four other supermarkets too, and you'll be surprised which was my overall favourite.

Throwing a kids' birthday party can be rather stressful, from booking a venue to deciding which kids' party food ideas to pick, from presents to the guest list - it's never-ending, and that's where buying a shop-bought birthday cake can come in handy - especially if your little one is a fan of a chocolate caterpillar cake

Over the years as a food writer, I have tried and tasted hundreds of food and drink products and consider myself a firm but fair critic. I worked in the Future Test Kitchen for nearly four years and helped to judge and coordinate a range of taste tests including the annual Easter and Christmas taste tests we feature on GoodtoKnow. So when I was asked to taste-test all the supermarket caterpillar cakes, I knew I’d be able to offer some useful insights when it came to choosing the best birthday cakes for kids as well as helping the parents out there make that big decision as to what caterpillar cake to buy for their little ones' birthday.

Now, how did I go about testing all these chocolate Swiss rolls I hear you ask? Well, I tasted a slice from each cake blind, which was the biggest factor in determining the overall winner. Once the winner was decided based on flavour, I cross-referenced notes I had taken on the cost, appearance, and serving size of each cake - and ta-dah, my winner was decided. 

PS... GoodtoKnow's Food Editor has tried and tested the best supermarket rainbow cakes  for those looking for more kids' birthday cake options

Where to buy a caterpillar cake

Best supermarket caterpillar cakes: tried and tested 

Waitrose Cecil The Caterpillar Cake

supermarket caterpillar cake taste test collage showing Cecil the caterpillar cake from Waitrose

(Image credit: Jessica Ransom)

Best supermarket caterpillar cake

RRP: £8.50 | Serves: 12 | Weight: 706g | Order: Online or in-store

Cecil won the blind taste test and was also one of the best-finished cakes in terms of decoration and appearance. This cake had nine layers alternating from cake to buttercream and they were impressively even.

The distribution of buttercream filling was also very consistent and gave a very satisfying swirl cross-section when sliced. Of all the cakes, Cecil had the least-dry texture which I think was in part thanks to all the layers.

The chocolate coating was smooth and neatly finished with an attractive drizzle of white chocolate across the top and sides. I used a serrated knife and it was easy to achieve clean slices with most of the chocolate coating staying intact and stuck to the cake.

I liked the white chocolate face and thought the tongue was cheeky and playful. The detailing on the eyes was nice, although I personally would have preferred chocolate as I don’t enjoy icing or sugar decorations as much.

The crunchy coated chocolates on the top were distributed in a three-two formation and added a nice bit of texture. I would have liked it if there were more of these as it didn’t feel very generous.

Cecil The Caterpillar Cake - £8.50 - Waitrose & Partners

Aldi Cuthbert The Caterpillar Cake

supermarket caterpillar cake taste test Cutherbert

(Image credit: Jessica Ransom)

Cheapest supermarket caterpillar cake

RRP: £5.49 | Serves: 12 | Weight: 716g | Order: In-store and online for Click & Collect orders

Cuthbert was the runner-up in the blind taste test and also turned out to be the cheapest of all the cakes which is impressive!

The buttercream was smooth and had a nice intense chocolate flavour. The chocolate shell coating was a little fragile and thin. It cracked a lot more than other cakes when sliced. It had six distinctive layers of cake and buttercream filling, although the distribution wasn’t as even as others.

The white chocolate feet are a cute size and I liked the generous scattering of colourful mini Smartie-like treats on top.

I thought the face on Cuthbert had a charming expression and I liked the detail of the eyes, nose, and adorable bow tie. The ridges for Cuthbert are created using thicker portions of buttercream which is a welcome choice as the buttercream was one of the tastiest parts of the cake.

The sponge looked a little dry at first glance but had an enjoyable mouthfeel and the mini chocolate decorations added a nice crunchy contrast in texture.

Cuthbert The Caterpillar Cake - £5.49 - Aldi

Asda Letty The Caterpillar Cake

supermarket caterpillar cake taste test

(Image credit: Jessica Ransom)

Best alternative decorations

RRP: £8 | Serves: 12 | Weight: 677g |Order: Online or in-store

Letty stood out from the lineup because it was the only caterpillar cake without a white chocolate face or feet. Instead, the face and feet are made from brightly coloured icing which is great for those with a sweet tooth.

I really liked the expression on Letty’s face and thought the red nose was a cute and unique detail.

Instead of decorating the top of the cake with Smartie-like chocolates, Letty has a mixture of colourful sprinkles and sweet edible balls. I thought this was a nice change from the traditional line up and also liked the raised squiggle pattern on the back of Letty instead of the classic grooves.

Letty came third when tested on flavour alone. The buttercream was glossy, smooth, and had a nice chocolate flavour though it wasn’t as rich as Cecil or Cuthbert. The sponge was a little dry but the cake had nice even layers.

Letty The Caterpillar Cake - £8 - View at Asda

Tesco Slinky The Caterpillar Cake

supermarket caterpillar cake taste test

(Image credit: Jessica Ransom)

Best variety of sweet decorations

RRP: £7.50 | Serves: 12 | Weight: 668g |Order: Online or in-store

Slinky was by far the most generous when it came to decorations. It had a white chocolate drizzle, white chocolate feet, an orange icing face, mini crunchy coated chocolates, and lots of sweet, fruity sugar crunchy bits too.

The buttercream had a wet, gooey texture but it lacked any real flavour. The sponge was quite dry and although it had a sweet taste, it was difficult to find any chocolate notes.

The milk chocolate shell was a little thicker than the other cakes and had a nice smooth texture. Overall the chocolate reminded me a lot of advent calendar chocolates and it left a slightly artificial taste in my mouth. However, I’m sure those with a sweeter preference to mine would enjoy the cake.

Slinky The Caterpillar Cake - £7.50 - View at Tesco

Marks and Spencer Colin The Caterpillar Cake

supermarket caterpillar cake taste test

(Image credit: Jessica Ransom)

Best tasting white chocolate decorations

RRP: £9 (£8.50 from Ocado) | Serves: 10 | Weight: 725g | Order: In-store or online via Ocado

The original caterpillar cake was the longest of the caterpillar cakes at 28cm long and 8cm wide. Despite this, it only serves 10 according to the box, which is the least of all the cakes.

I found the cake to be a little dry and the distribution of buttercream was a little uneven between the layers of cake. The ridge of the cake, which is achieved with the use of thicker layers of buttercream, helped with the overall texture and mouthfeel but slices without this would be a lot drier.

The white chocolate for the feet and the face was the tastiest of all the cakes I tried. It had a pleasant sweet but creamy flavour and didn’t have a chalky texture which others did. The white chocolate feet and face were also bigger and thicker compared to other cakes.

Colin has a nice thick milk chocolate shell and a classic design which is charming. It would be nice if there were more crunchy-coated chocolates on top of the cake but I liked the white chocolate button on the tail end of the cake.

Colin The Caterpillar Cake - £8.50 - View at Ocado

Sainsburys Wiggles The Caterpillar Cake

supermarket caterpillar cake taste test

(Image credit: Jessica Ransom)

Caterpillar cake with the most servings / Best dupe of Colin the caterpillar design

RRP: £7.50 | Serves: 14 | Weight: 698g |Order: Online or in-store

Wiggles can serve up to 14 people according to the box. The cake was 25cm long which was the third longest of the cakes. The slices would have to be quite thin in order to get 14 portions but it could be possible. I suspect part of the serving suggestion is to help with the nutritional figures as each portion works out to be under 200 calories.

This cake was the closest in design to the original Colin the caterpillar cake. It had white chocolate feet and a face with a very similar expression and design. The only difference between the face of Wiggles and Colin is that Colin has a pink detail on his tongue.

I like the addition of sprinkles alongside the crunchy coated chocolates, which had a fruity, tangy flavour. The ridge details on the back of the caterpillar were a little uneven but the milk chocolate shell was evenly distributed and had a melt-in-the-mouth texture.

Wiggles The Caterpillar Cake - £7.50 - View at Sainsbury’s

How I tested the best caterpillar cakes

supermarket caterpillar cake taste test

(Image credit: Jessica Ransom)

In order to rank the supermarket cakes fairly, I cut a slice from the middle of each caterpillar and arranged them on plates with a number for each different cake.

I chose a slice from the middle as this would promise the most even layers of cake and distribution of chocolate and buttercream. The middle of the cake should also, in theory, be the most moist. As with any loaf cake or classic Swiss roll, the edges cook the quickest in the oven and have a tendency to dry out the quickest once baked too. 

I drew a table on a piece of paper with two columns and six rows. I made notes on each cake and cleansed my palette with water and crackers between each tasting. Once I had tasted all the cakes, I then compared my tasting notes with observations I had made earlier in the day about the cakes appearance, cost, and serving size.

To judge the appearance I looked at how neatly each cake was finished, the distribution of edible decorations, and if the face of the caterpillar was cute or perhaps a little creepy...

I also noted how many layers each cake had, how evenly the distribution of filling was to the cake, and how generously the cake was decorated with the crunchy coated chocolates or sprinkles.

Some of the cakes gave a weight as well as the serving size. The weights in the title of each listing in this taste test, are based on the cakes weighed on the serving board. 

supermarket caterpillar cake taste test

(Image credit: Jessica Ransom)

Do any other supermarkets sell caterpillar cakes?

Iceland has an Iceland Celebration Caterpillar Cake which, like the other cakes, features a chocolate sponge cake filled with buttercream and covered in milk chocolate and edible decorations. 

If you fancy a pink theme, M&S sells Connie The Caterpillar Cake which is similar to Colin but is decorated with pink and white sugar hearts, pink sugar-coated chocolate beans, and pink chocolate footsies.

Tesco’s pink caterpillar is called Fuzzy and costs the same as Slinky. 

Co-op sold a large caterpillar cake called Charlie in the past but at the time of writing, we can’t find it online or in stores. If you need something vegan though, they sell a pack of four mini Vic The Vegan Caterpillar Cakes

Asda has a free-from version called Frieda, Tesco’s option is called Stripey, and Sainsbury’s free-from-cake is called Eric

Morrisons have Morris The Caterpillar cake which serves 12 and has a white chocolate face and feet plus sprinkles and crunchy coated chocolates for decoration. 

Which supermarket made the first caterpillar cake?

The first caterpillar cake was launched in 1990 and was the creation of Marks & Spencer. When Colin first launched he didn’t have feet and the iconic white chocolate face was instead made from fondant. 

Which supermarket caterpillar cake has the most calories per slice?

Colin is the most calorific cake at 283 calories per slice, 7.8g saturated fat, and 28.9g sugars. This could partly be due to the fact that slices of Colin are bigger than other cakes as Colin serves 10 whereas most of the cakes serve 12. 

Wiggles from Sainsbury’s had the least calories per slice at 199 calories, 5.2g saturated fat, and 18.4g sugars. 

The second most calorific caterpillar cake was Cecil from Waitrose & Partners at 259 calories, followed by Aldi and Tesco at 222 calories and Asda at 212 calories.

Are caterpillar cakes a British thing?

Swiss roll-shaped cakes that are decorated to look like a caterpillar became a big hit in the UK in the Nineties and are now part of popular British culture. Although Marks and Spencer were the first supermarkets to launch a cake, as this taste test has proven, they now have a lot of competition. 

If all this talk of cake has given you the urge to do some home baking, this chocolate cake recipe is a great place to start. You might also like these Frozen birthday cake ideas or perhaps these Bluey birthday cake ideas are more suited to your little one. 

Jessica Ransom
Senior Food Writer

Jessica is a freelance food writer, stylist and recipe tester. She previously worked as Senior Food Writer at Future. While at Future Jessica wrote food and drink-related news stories and features, curated product pages, reviewed equipment, and developed recipes that she then styled on food shoots. She is an enthusiastic, self-taught cook who adores eating out and sharing great food and drink with friends and family. She has completed the Level 1 Associate course at the Academy of Cheese and is continually building on her knowledge of beers, wines, and spirits.