Mary Berry’s bonfire chocolate traybake is a dense, fudgy chocolate sponge made with melted dark chocolate, ground almonds and butter, baked at 180°C (160°C fan) for 25 to 30 minutes in a 23×30cm tin. It makes 20 squares and needs nothing more than a dusting of icing sugar.
Berry published this in Foolproof Cooking (2016) and describes it as “a light cake, really moist owing to the addition of ground almonds.” She designed it for Bonfire Night, “perfect for packing into a box and sharing with family and friends at an event.” No icing is needed, which makes it the only chocolate traybake in her books you can cut and pack straight from the tin.
The method is completely different from her other chocolate traybakes. Instead of dissolving cocoa powder in water, Berry melts whole dark chocolate with butter, stirs in the sugar, then adds eggs one at a time. Ground almonds replace half the flour, which gives the sponge a denser, more truffle-like texture that stays moist for days.
Mary Berry Bonfire Chocolate Traybake
Course: DessertCuisine: BritishDifficulty: Easy20
servings15
minutes25
minutes163
kcal45
minutesBerry’s tip explains why this cake lasts: “Adding ground almonds to a chocolate cake mixture makes it extra moist, which means it keeps well.” It can be made 2 days ahead and freezes well, so you can bake it midweek and eat it at the weekend.
Ingredients
225g (8 oz) dark chocolate (no more than 40–50% cocoa solids), broken into squares
100g (4 oz) butter, cut into small cubes, plus extra for greasing
100g (4 oz) caster sugar
3 eggs
75g (3 oz) self-raising flour
75g (3 oz) ground almonds
1 tsp baking powder
Directions
- Preheat: Set the oven to 180°C/160°C fan/Gas 4 (350°F). Line a 23×30cm (9×12 in) traybake tin with foil and grease it generously with butter.
- Melt the chocolate: Place the chocolate and butter in a heatproof bowl set over a pan of hot water and leave until just melted. Once melted, add the sugar and stir to combine, then set aside to cool slightly.
- Mix the batter: Add the eggs, one at a time, to the melted chocolate mixture, beating after each addition. Fold in the flour, ground almonds and baking powder and then pour evenly into the prepared tin.
- Bake: Bake in the oven for 25–30 minutes until the mixture is just set. Allow to cool in the tin before cutting into 20 squares.
Notes
- Calories: 225g dark chocolate (1,229) + 100g butter (717) + 100g sugar (387) + 3 eggs (234) + 75g SR flour (259) + 75g ground almonds (431) = 3,257 ÷ 20 = 163 kcal per square
FAQs
Why does Berry use melted chocolate instead of cocoa powder here?
Her Iced Chocolate Traybake from Ultimate Cake Book (2003) and Rich Chocolate Tray Bake from Mary Berry Cooks (2014) both dissolve cocoa powder in hot water, which gives a lighter, more cake-like sponge. Melting whole chocolate with butter creates a denser, fudgier result because the cocoa butter in the chocolate coats the flour proteins and restricts gluten development.
The flavour is richer too. Berry specifies “dark chocolate with no more than 40-50% cocoa solids,” which is milder than the 70% bars some recipes call for. She uses this same range across her chocolate recipes, writing elsewhere that higher cocoa solids “can be too bitter” for most home baking. The 40-50% range gives depth without harshness.
Why do ground almonds make this cake moister than Berry’s other traybakes?
Berry’s own Foolproof Tip answers this directly: “Adding ground almonds to a chocolate cake mixture makes it extra moist, which means it keeps well.” Ground almonds hold onto fat and moisture during baking in a way that flour can’t. Flour dries out over time as the starch goes stale, but almonds don’t stale the same way.
She uses the same principle in her Baking Bible’s Very Best Chocolate Fudge Cake, which is “a very close-textured fudgy cake” where “ground almonds give the flavour and texture.” The 75g of ground almonds here replaces half the flour, which is enough to change the texture noticeably without making the cake heavy or cloying.
Can I add icing to this cake or should I leave it plain?
Berry says “no icing is needed — just dust with icing sugar to serve, if you like.” The cake is designed to be rich enough on its own, and adding a chocolate icing on top of a melted-chocolate sponge would push it into brownie territory. The icing sugar dusting lightens the look without adding sweetness.
That said, if you’re serving it as a dessert rather than packing it for Bonfire Night, a spoonful of crème fraîche or a pour of single cream alongside each square works well. I’ve also drizzled melted white chocolate over the top in thin lines, which adds contrast without overwhelming the dark chocolate base.
How is this different from Berry’s other chocolate traybakes?
It’s the simplest of the three. The Iced Chocolate Traybake from Ultimate Cake Book (2003) uses cocoa powder dissolved in water, soft margarine, and has a poured chocolate icing with icing sugar on top. The Rich Chocolate Tray Bake from Mary Berry Cooks (2014) also uses cocoa but adds a milk chocolate ganache feathered with white chocolate. Both are lighter, more cake-like sponges.
This Bonfire version is denser and more intense because it uses melted chocolate instead of cocoa, and ground almonds instead of extra flour. It’s also the only one that doesn’t need icing, which makes it the most practical for outdoor events. Berry clearly designed each one for a different situation: lunchbox, birthday party, and bonfire.
How do I store bonfire chocolate traybake?
Berry says it can be made up to 2 days ahead and freezes well. The ground almonds are why it keeps longer than her other traybakes, holding moisture in the crumb even after two days at room temperature. Store the squares in an airtight tin with baking parchment between the layers.
For freezing, wrap individual squares in cling film and then stack them in a freezer bag. They defrost at room temperature in about an hour and taste almost identical to freshly baked. I’ve kept them frozen for six weeks without any loss of texture, which makes them a reliable standby for unexpected guests.
What chocolate should I use for this cake?
Berry is specific: “dark chocolate, no more than 40-50% cocoa solids.” That rules out the very dark bars marketed for baking, which are often 70% and above. She writes elsewhere in Mary Berry Cooks that you should “use a good-quality bar of chocolate with 40-60 per cent cocoa solids for a rich flavour,” and warns that higher percentages can taste bitter, especially to children.
Look in the baking aisle rather than the confectionery aisle. Baking chocolate has a higher cocoa butter content, which melts more smoothly and combines better with the butter. If you can only find eating chocolate, something like Bournville (36%) will work but the flavour will be slightly milder than Berry intended.
