Mary Berry Chocolate Chip Traybake

This one’s a bit of a sleeper hit. It doesn’t shout. There’s no fancy swirl or shiny topping. But make no mistake—this chocolate chip traybake delivers. It’s the kind of cake that disappears before you’ve even had time to wrap up the leftovers.

The first time I made it, I underbaked it slightly because the centre looked done (spoiler: it wasn’t). And I got cocky with the chocolate chips—added extra and they all sank. Second time, I held back, mixed them in gently, and watched it rise evenly with little pools of melty chocolate holding their ground. The mascarpone icing? Cool, creamy, and exactly what this rich, cocoa sponge needs.

This is one of those bakes that’ll quietly become a regular.

WHY THIS ONE WORKS SO WELL

The cocoa and boiling water base means the chocolate flavour actually comes through—it’s deeper than your standard sponge. You’re not just colouring it brown; you’re building flavour from the start.

And then you’ve got the texture: soft, light, slightly fudgy thanks to the chips, but still sliceable without crumbling. The mascarpone topping keeps it from feeling too rich. It’s not overly sweet—just creamy, cool, and perfect against the sponge.

INGREDIENTS + WHY THEY MATTER

Cocoa Powder (4 tbsp) – Needs to be sifted and bloomed in boiling water. This wakes up the flavour.
Boiling Water (4 tbsp) – Makes the cocoa mixture smooth and intensifies the taste.
Baking Spread (225g) – Straight from the fridge works fine. Easier than softening butter.
Caster Sugar (225g) – Keeps the crumb fine and not overly dense.
Self-Raising Flour (225g) – Lifts the batter without needing extra ingredients.
Baking Powder (1 tsp) – A little boost for extra lightness.
Dark Chocolate Chips (100g) – Use good quality. I find 54–60% cocoa works best.
Mascarpone (250g) – Soft and creamy. Doesn’t overpower.
Icing Sugar (3 tbsp) – Just enough to sweeten the icing without making it sickly.
Vanilla Extract (1 tsp) – Gives warmth and rounds out the flavour.
Cocoa Powder (for dusting) – Optional, but adds that finished look.

MAKING IT YOURS (WITHOUT RUINING IT)

Want more chocolate? Swap half the chips for chunks—they give bigger bursts.
No mascarpone? You can use cream cheese, but the flavour will be tangier.
Need it nut-free? Just check your chocolate chips—some brands aren’t.

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

What Went Wrong	Why It Happens	How to Fix It
Chips sank to the bottom	Batter too thin or overmixed	Gently fold in chips at the end
Sponge too dry	Overbaked or oven too hot	Check at 30 mins and use middle shelf
Icing split	Mascarpone too cold	Let it soften slightly before mixing

HOW TO MAKE MARY BERRY’S CHOCOLATE CHIP TRAYBAKE

1. Preheat and Prep
   Set oven to 180°C (160°C fan). Grease and line a 30x23cm traybake tin.
2. Make the Cocoa Base
   Mix sifted cocoa powder and boiling water until smooth. Let it cool slightly.
3. Mix the Batter
   Add baking spread, sugar, eggs, flour, baking powder, and the cocoa mix to a bowl. Beat until just smooth. Gently fold in the chocolate chips.
4. Bake
   Spoon into the tin, level it out, and bake for about 35 minutes. It’s done when the sponge springs back and a skewer comes out clean.
5. Cool Completely
   Leave the cake in the tin on a wire rack until fully cool.
6. Make the Icing
   Mix mascarpone, icing sugar, and vanilla extract until smooth and thick. Spread over the cooled cake. Dust with cocoa powder if using.
7. Serve
   Slice into squares or fingers—whatever suits your crowd.

TIPS FROM MY KITCHEN

I mix the cocoa and boiling water first and let it cool while prepping everything else—it thickens slightly and blends better.
Don’t skip the sifting—it makes both the sponge and icing smoother.
If I’m serving this the next day, I wait to ice it until the morning—it keeps the sponge soft.

STORAGE + SERVING

Keeps: 4–5 days in the fridge, covered
Freezes: Sponge only—freeze in slices, un-iced, for up to 3 months
Serve with: A cold glass of milk, a scoop of vanilla ice cream, or straight from the tin with a spoon

FREQUENTLY ASKED QUESTIONS

Q: Can I use milk chocolate chips?
You can, but the bake gets sweeter overall. Stick to dark if you want that nice balance.

Q: Can I make the icing ahead?
Yes—store it in the fridge, then stir before using. Let it soften a bit before spreading.

Q: Why is my icing too soft?
Likely overmixed or the mascarpone was too warm. Try chilling it briefly before spreading.

Try More Recipes:

• Mary Berry ​Chocolate Chip Brownies
• Mary Berry Chocolate Chip Shortbread
• Mary Berry Double Chocolate Chip Muffins