Ingredients

Step by step

1. For the pastry, put the cocoa, flour, a pinch of salt and the icing sugar into a food processor and whiz until uniform in colour. Add the diced butter and pulse until it looks like chocolate sand. Add 2-3 tablespoons of chilled water and pulse again until it forms a ball. Flatten, wrap and chill for 30 minutes to rest and firm up.
2. For the caramel, put the maple syrup, butter and cream into a small pan on a medium heat. Bubble for 8-10 minutes until thickened and glossy. The caramel will change from looking foamy to large bubbles. Remove from the heat and cool to room temperature. Preheat the oven to 200°C, fan 180°C, gas 6.
3. Roll out the pastry to 3-4mm thick on a cocoa-and-flour dusted work surface, and use to line a 23cm tart tin. Trim off the excess pastry, add a piece of scrunched-up baking paper and fill with baking beans. Bake for 12 minutes, then remove the paper and beans, and bake for another 5-8 minutes until it looks dry and completely cooked. Leave to cool completely.
4. Stir the cooled caramel, reserve 1 tablespoon for the topping, then pour the rest into the pastry case and chill for 2 hours until firm. Once you’re happy the caramel is set, heat the cream in a small pan on a low heat until hot, but not simmering. Tip the finely chopped chocolate into a heatproof bowl, and pour in the hot cream. Mix well until thick and smooth. Leave to cool to room temperature, then pour over the chilled caramel, smoothing over with a spatula if you need to, and chill again for at least 3 hours or until the tart is completely firm.
5. To serve, drizzle with the leftover caramel sauce (warm it briefly in the microwave if it has set), and sprinkle the sea salt flakes on top. You only need a small slice of this tart, as it is really rich. Serve with crème fraîche and/or berries if you’d like to cut through the richness.