Mary Berry Mocha Cake

I first made this Mocha Cake on a gloomy Tuesday when my coffee machine broke and I needed something—anything—with caffeine in it. It was meant to be a quick bake just to get me through the afternoon slump. Spoiler: I ended up eating two slices before dinner.

But here’s the thing—I used margarine straight from the fridge (per Mary’s instructions), and honestly, I thought it would never come together. The batter looked a bit curdled at first, and I panicked. But then it baked up beautifully: golden edges, that deep coffee aroma, and a sponge that was somehow both fluffy and rich.

If your buttercream ever seizes or your sponge turns rubbery, I’ve been there. Let me show you how I fixed that—and why I’ll be baking this again every time I need a hit of chocolate and caffeine.

The Secret Behind This Bake

This cake works so well because it’s balanced—deep coffee flavour, soft sponge, and that silky mocha icing that feels like a hug in frosting form.

• Coffee extract is key here. Most coffee cakes just toss in instant granules, but Mary calls for proper extract—and she’s right. It gives a bold, clean flavour without bitterness.
• The sponge uses margarine straight from the fridge. Sounds odd, but it actually helps keep the crumb moist and tender without that greasy aftertaste you sometimes get with butter.
• And the drinking chocolate in the icing? Genius. It softens the intensity of the coffee and makes the whole thing taste like a mocha from a posh café.

INGREDIENTS + WHY THEY MATTER

• Self-raising flour – The built-in lift is what gives you that classic Mary Berry airy crumb. Plain flour with baking powder didn’t rise as evenly when I tested it.
• Superfine sugar – Dissolves quickly for a smoother sponge. I tried granulated once—it left tiny gritty bits.
• Chilled margarine – Keeps the structure light. Room-temp butter made the mix greasy and heavy.
• Coffee extract – Pure flavour without grit. I used Nielsen-Massey—strong but smooth.
• Baking powder – Just a touch for extra lift.
• Butter (for icing) – I once tried margarine here and regretted it. You need the flavour and texture of real butter for the icing.
• Drinking chocolate – Adds depth and softness to the mocha icing without overpowering the coffee.

Making It Yours (Without Ruining It)

• No eggs? I tested it with 3 tbsp aquafaba per egg. Texture was slightly denser, but still tasty.
• Gluten-free? Swap for a GF self-raising blend (I used Doves Farm) + ½ tsp xanthan gum. Let it rest 10 mins before baking.
• Dairy-free? Use Flora Plant Butter for both sponge and icing. Works a treat, though the icing sets slightly softer.
• Add-ins: Toasted walnuts between the layers give it a coffee-walnut twist. Just keep them chopped fine or they’ll sink.

MISTAKES I’VE MADE (AND HOW TO AVOID THEM)

What Went Wrong	Why It Happens	How to Fix It
Sponge sank in middle	Oven door opened too early	Wait at least 25 mins before peeking
Icing split	Butter too cold or sugar added too fast	Let butter soften fully, add sugar gradually
Coffee flavour too weak	Used instant granules instead of extract	Stick to liquid extract for real depth
Crumb was dense	Overmixed the batter	Mix until just combined—no more!

HOW TO MAKE MARY BERRY’S MOCHA CAKE

1. Preheat & prep: Set oven to 180°C/160°C fan (350°F/320°F fan). Grease and line two 8-inch sandwich tins.
2. Mix the batter: Beat all cake ingredients in one bowl with an electric mixer. It may look curdled if margarine’s very cold—don’t worry. Keep going until smooth.
3. Bake: Divide batter evenly. Bake 30–35 mins until risen and springy. Cakes should shrink slightly from sides when ready.
4. Cool: Turn out onto a wire rack. Peel off paper and cool completely.
5. Make the icing: Beat softened butter, sifted icing sugar, coffee extract, and drinking chocolate until fluffy. If too stiff, add a drop of milk.
6. Assemble: Spread half the icing on one cake, top with second sponge, and cover the top with remaining icing.
7. Decorate: Use a fork or knife to mark the top. Sprinkle with chocolate shavings.

TIPS FROM MY KITCHEN

• I microwave the margarine for 5 seconds just to soften the edges—makes mixing smoother.
• I always sift the drinking chocolate with the icing sugar—no lumps.
• Use an offset spatula for the top icing—it gives that café swirl look.
• I chill the iced cake for 15 mins before slicing—firmer, cleaner cuts.

STORAGE + SERVING

• Keeps: 4 days in the fridge, in a lidded container.
• Freezing: Wrap slices in cling film, then foil. Freeze up to 2 months. Thaw overnight in fridge.
• Serve with: A flat white or espresso, fresh raspberries, or a scoop of vanilla gelato. Heaven.

FAQs – Real Query Answers

Q: Can I use instant coffee instead of extract?
A: You can, but it’s not the same. If you must, dissolve 1 tbsp instant coffee in 1 tbsp boiling water. Still not as smooth as extract though.

Q: Why margarine instead of butter?
A: It’s Mary’s trick! Cold margarine keeps the sponge soft and stable. Butter made mine greasy and sunk slightly.

Q: Can I make this as a traybake?
A: Yes! Use a 9×13-inch tin and bake for around 25–30 minutes. Skip the sandwiching—just spread icing on top.

Q: Does it taste like strong coffee?
A: Not overly. More like a mellow mocha—coffee and chocolate in balance. Even my “no coffee after 2pm” friend loved it.

Try More Recipes:

• Mary Berry Victoria Sandwich
• Mary Berry Honey Cake
• Mary Berry Milk Chocolate Cake
• Mary Berry Fruit Cake