Grease 4 small pudding molds with butter and dust the insides with coco powder. Refrigerate for 30 minutes.

Melt the chocolate and butter in a bowl over a pan of simmering water. Set aside

Meanwhile, beat eggs, egg yolks and caster sugar together for several minutes until thick, pale moussey consistency.

Then carefully fold the chocolate mixture into the egg and sugar mix. Finally blend flour and espresso powder and fold in carefully so as not to knock any air out of the mix.

Divide among prepared molds. Place in the fridge until firm. You can make the puddings up to 24 hours in advance and leave them in the fridge until you are ready to cook them.

Preheat the oven to 350F. Place the puddings on a baking tray and bake for 8 minutes, or until the puddings are risen but not cracked. Turn out the puddings on to individual plates and serve, with whipped cream or ice cream

FILLING VARIATIONS (ENOUGH FOR ONE CAKE): 2 teaspoons COLD salted caramel, store-bought or homemade 2 teaspoons Nutella or your favorite chocolate hazelnut spread 2 teaspoons WELL SET Peanut Butter Cup filling (recipe below), but creamy peanut butter straight from the jar may be substituted, but it will taste less sweet and much richer. Do NOT use natural-style peanut butter in both case PEANUT BUTTER CUP FILLING: 1 teaspoon creamy peanut butter (Do NOT use natural-style) 1 teaspoon butter 1 teaspoon powdered sugar OTHER FILLING IDEAS: Dulce de leche Milk, dark or white chocolate ganache Caramel filled chocolate, like Rolo Chilled butterscotch sauce Fruit preserves or puree