Ingredients

140g plain flour, plus extra for dusting

50g butter, cut into pieces

2 tsp cocoa powder

1 tbsp icing sugar

1 tbsp rapeseed oil

1 medium egg yolk

Half-fat crème fraîche, to serve (optional)

100g dark chocolate, 70% cocoa solids, very finely chopped

1 tbsp cocoa powder, plus extra ½ tsp for sifting

¾ tsp coffee granules

½ tsp vanilla extract

2 tbsp semi-skimmed milk

2 medium egg whites

2 tbsp dark muscovado sugar

85g half-fat crème fraîche

Instructions

Step 1: Tip the flour into a mixing bowl and remove 2 tsp (this will be replaced by cocoa later). Add the butter and rub into the flour until the mixture resembles fine breadcrumbs.

Step 2: Sift in the cocoa powder and icing sugar. Using a round-bladed knife, stir in the rapeseed oil, egg yolk, and 1½ to 2 tbsp cold water until the dough comes together. Gather gently into a ball.

Step 3: Roll out the dough on a lightly floured surface to fit a 20cm round x 3.5cm-deep loose-bottomed flan tin. Ease the pastry into the tin, leaving a slight overhang. Lightly prick the base with a fork and chill for about 10 minutes.

Step 4: Heat the oven to 190°C/170°C fan/gas 5. Line the pastry with foil and fill with baking beans. Blind-bake for 15 minutes until set, then remove the beans and foil and bake for another 10 minutes until the base is cooked.

Step 5: Remove the pastry case from the oven, trim the overhanging pastry for a flat edge, and leave to cool completely.

Step 6: To prepare the filling, place the finely chopped chocolate in a bowl that fits over a pan of simmering water without touching it. Mix the cocoa powder, coffee granules, and vanilla with the milk, then pour over the chocolate.

Step 7: Set the bowl over the simmering water and stir until the chocolate starts to melt. Remove the pan from the heat but keep the bowl over the water, stirring occasionally until fully melted and thick.

Step 8: Stir in 2 tbsp boiling water to thin the chocolate mixture until silky smooth. Remove the bowl from the heat and allow to cool slightly.

Step 9: Whisk the egg whites until stiff peaks form, then whisk in the dark muscovado sugar until thick and glossy.

Step 10: Fold the crème fraîche into the cooled chocolate mixture. Gently fold one-third of the egg whites into the chocolate, then carefully fold in the remaining whites in two additions until well combined.

Step 11: Remove the pastry case from the tin and place on a serving plate. Spoon the chocolate filling into the case and spread evenly.

Step 12: Chill the tart in the fridge for about 3 hours or overnight before serving. Dust with extra cocoa powder and serve with half-fat crème fraîche if desired.

Note: This tart contains raw eggs. Pregnant women, the elderly, babies, toddlers, and anyone unwell should avoid consuming raw or partially cooked eggs.

Tips & Variations

For a nutty twist, add finely chopped toasted hazelnuts to the chocolate filling before chilling.

If you prefer, swap rapeseed oil for melted coconut oil in the pastry for a subtle flavor change.

Use decaffeinated coffee granules if sensitive to caffeine while maintaining depth of flavor.

Ensure the mixing bowl does not touch the water during chocolate melting to prevent overheating and seizing.

FAQs

Can I use a different kind of chocolate?

Yes, you can use chocolate with slightly less or more cocoa content, but 70% cocoa solids provide the ideal balance of richness and bitterness for this tart.

Is there an egg-free alternative for this tart?

This recipe relies on egg whites for a light, mousse-like texture in the filling, so substituting eggs is challenging. For an egg-free version, consider a chocolate ganache filling made with cream and chocolate instead.