When it comes to chocolate caterpillar cakes, there has long been a rivalry between two major supermarket chains. This competition began in 2021 when one of them took legal action against another over a cake that was seen as too similar to an existing product. The dispute eventually led to a settlement, but now it seems a new battle is brewing. In a recent blind taste test conducted by consumer champions, the best chocolate log cake was revealed — and it wasn’t from either of the usual contenders.
In a surprising twist, Colin the Caterpillar was actually named the ‘worst’ among nine different chocolate log cakes in the test. The results were shocking for many, especially given the brand’s reputation. But the winner of the title was Waitrose’s Cecil Chocolate Sponge Cake, which scored highly with a 78% overall rating.
Cecil, priced at £9.50, was the largest cake in the test at 744g, making it more cost-effective than its competitors. It received praise for its thick chocolate shell and perfect sponge-to-buttercream ratio. The cake was also described as remarkably moist, which some found appealing while others might not have liked it.
Following closely behind in joint-second place were Co-op’s Party Time Charlie Chocolate Cake and Sainsbury’s Birthday & Celebration Wiggles the Caterpillar Cake. Both scored 73%. Charlie was the priciest option but impressed testers with its rich chocolate flavour and buttercream. Meanwhile, Wiggles was noted as a great lookalike for Colin but without the high price. However, its sponge lacked the moisture of the top contender.
Aldi’s Cuthbert the Caterpillar Cake and Morrisons’ Morris the Caterpillar Celebration Cake both scored 72%, placing them in third. Cuthbert was praised for its creamy texture, while Morris had the lowest sugar content and the best-rated buttercream.
Asda’s Letty the Caterpillar Cake came next, followed by Lewis & Green’s Caterpillar Celebration Cake, which was available at Iceland for £4.50. At the bottom of the rankings were Tesco’s Slinky Caterpillar Cake and M&S’s Colin the Caterpillar Cake, which finished last with a score of 64%.
Tasters found Colin to be too dry and noted that the chocolate flavour was too weak. Additionally, it was found to be the least healthy cake, with the highest levels of sugar and fat per 100g.
What does M&S have to say?
M&S responded to these findings by highlighting that Colin was named the nation’s best caterpillar cake in an independent YouGov poll from March 2026. They also pointed out that Colin has the highest chocolate content on the market.
An M&S spokesperson said: “Colin the Caterpillar is the UK’s number one caterpillar cake – over a million are sold every year. Made and finished by hand in the UK for over 35 years, it leads the market on quality and taste. It has the highest chocolate content on the market at 39.5%, with milk chocolate made from 31% cocoa solids and 100% Fairtrade cocoa.”
How were the cakes tested?
A panel of 75 people participated in a blind taste test in March 2026. The group consisted of people from various age groups across the UK who enjoy this type of celebration cake. Each cake was sampled in a private booth, ensuring no influence from others. Tasters rated the cakes on taste, texture, aroma, and appearance, with final scores based on 50% flavour, 30% appearance, 10% aroma, and 10% texture.
Natalie Hitchins, head of home products and services at Which, added: “For many of us, a caterpillar cake is the ultimate nostalgia trip, but our test shows that you shouldn’t let brand fame dictate your birthday budget. While M&S created the category, rivals like Waitrose and even budget-friendly Iceland are now delivering a better slice of the action. Whether you’re looking for the best taste or the best price, there are better options out there than the original Colin.”
More supermarket own-brand taste tests:
- Supermarket own-brand Mini Eggs crowned better than Cadbury — and they’re 25p cheaper
- Supermarket hot cross buns ‘as good as M&S’ — but they’re more than £1 cheaper
- Supermarket own-brand chocolate biscuits voted better than McVitie’s — and they’re £1 cheaper
- Supermarket own-brand coffee crowned best in UK — beating Nescafé and Kenco
- Supermarket own-brand cheese crowned best in the UK — better than Cathedral City
Do you have a story to share? Get in touch by emailing [email protected]. Comment now. Add as a Preferred Source on Google. Add as preferred source. Sign up to ‘s The Slice newsletter for your guide to what’s on in London, with trusted reviews, offers and giveaways.
