- The Startup Slice
- Posts
- 🚀 Your Weekly Slice of UK Consumer Startups #22
🚀 Your Weekly Slice of UK Consumer Startups #22
Meet the dark chocolate startup teaching a masterclass in branding
The Startup Slice
September 28, 2025 • Estimated Reading Time: 7 minutes
Hey 👋
We’re back with a weekly roundup of the UK’s most exciting consumer startups. OLLY’S challenge olive haters, Nuud Gum racks up millions of views, and The Root’s co-founder takes on a new alter ego.
We also visited lunch! (trade show) this week so stay tuned for our post covering some of our favourite brands.
And for this week’s playbook, we sat down with Ella McKay, co-founder of FATSO, the dark chocolate brand making serious waves with their chunky, cheeky, chocolatey goodness 🍫.
📱 From the Feed
 OLLY’S sampling at their ‘OLLING station | 🫒 OLLY’S epic sampling: only 40% of the UK like olives so OLLY’s put up a billboard and polling station, to see how many OLLY’s lovers and haters there are. 🚀 Tesco Accelerator cohort: The new lineup is here, backing the next wave of UK consumer innovation. |
👀 ICYMI: Brand Moves Worth Watching
 Will Englander, founder of The Root Co, aka the hangover hero | 🌱 Nuud Gum latest campaign racks up 30M views: #PoisonedByPlastic is putting gum’s microplastic problem in the spotlight. With 41 MPs backing their call for regulation, Nuud are proving startups can shift culture and policy. 🦸 The Root Co’s founder becomes a hangover hero: Will hit the streets in a superhero suit, “rescuing” Londoners from hangovers while spreading the word about recovery shots. 🚦 Oxford Street sampling opportunity: Ownership of Oxford Street is moving to TFL and brands like Fix8 Kombucha have been sampling to celebrate the iconic street becoming pedestrianised. |
💡 Bitesize Playbook: Co-founder of FATSO, Ella Mckay.
Dark chocolate is notoriously serious so we chat with Ella about how FATSO is making dark chocolate fun!
Ella Mckay, Co-founder of FATSO, ft. Morn’n Glory flavour
For those that might not know, what is FATSO?
We are the chunkiest, most delicious champions of dark chocolate. Bored of the seriousness of dark chocolate, FATSO is on a mission to show the world that dark chocolate can have just as much fun as milk chocolate, whilst retaining all the quality and ethical credentials that make eating our bars that much sweeter.
Where do your unique flavour ideas come from?
Our bonkers brains’ largely! Sometimes the personality or concept comes first. For example, Morn’n Glory (Cornflake, Toast & Marmalade) was a combination of the idea of chocolate for breakfast (always), a universal love of orange chocolate and a nostalgic memory for those chocolate cornflake cakes you had as a kid. Home Run was a little different: a celebration of salt and sweet, and Americana sports culture. Translated to salted pretzel, almond and honeycomb. So in short, they come from anywhere and everywhere!
How do you approach ethical sourcing and sustainability?
With sheer determination and no compromises. We met Luker (our sole cocoa supplier in Colombia) before we even had a brand name. I learned everything I now know about the cocoa world, and the complexities and challenges it faces through the team at Luker. They are a family run farming co-operative out in Colombia, growing and producing the most beautiful, award winning chocolate at the same time as ensuring fair and prosperous wages and treatment of farmers. Sourcing our chocolate from Luker was a no brainer, with their uncompromising approach to taste, quality, ethics and philanthropy. I then used my industry contacts in the UK to find our packaging producers. We went with Print 4, a sustainability obsessed, independently run printing company in Nottingham. They go above and beyond to limit our environmental impact through printing: from their recycling of water and material practices to their introduction of Carbon Negative Kelp ® black ink., and their bee meadow in their back garden!
The packaging really stands out in the dark chocolate space. What was the vision behind FATSO’s bold branding?
To create something as beautiful and premium as it was playful and witty. To show that to appeal to grown-ups and to an audience seeking quality, brands don’t need to be serious, muted and frankly boring. And to show that colourful doesn’t need to always be juvenile.
FATSO exists to disrupt, and the packaging is a huge part of that identity.
So what’s next for FATSO?
We’re just getting started and have big ambitions to be the true champions of dark chocolate. We are working on special edition flavours, new formats, fun collaborations with other like-minded brands. The list goes on.
Ultimately though, our mission is to get more great dark chocolate in more mouths.
Life is for living afterall, and that includes eating epic tasting chocolate, without compromises and most definitely without guilt!
FATSO King’s Ransom flavour
Thanks for reading this week’s edition! 🥳
📥 Been forwarded this? Sign up here to get the next edition.
📨 If this landed in spam, move us to your main tab.
🚀 The Startup Slice