For the ice cream:

• 300 ml (10½ fl oz) thin (pouring/whipping) cream
• 175 g (6 oz) sweetened condensed milk
• 2 tablespoons instant coffee granules
• 2 tablespoons coffee liqueur

For the cake:

• 225 g (8 oz) unsalted butter, softened
• 225 g (8 oz) caster (superfine) sugar
• 4 eggs
• 2 tablespoons full-cream (whole) milk
• 225 g (8 oz) plain (all-purpose) flour
• 3 tablespoons unsweetened cocoa powder
• 1 teaspoon baking powder

For the sauce:

• 150 g (5½ oz) dark chocolate
• 50 g (1¾ oz) lightly salted butter
• 250 ml (9 fl oz/1 cup) thin (pouring/whipping) cream

MAKE THE ICE CREAM. Combine all the ingredients in a mixing bowl and beat together with an electric beater until they have a lovely mousse-like consistency. Pour this mixture into a cold-resistant container and place it in the freezer for at least 5–6 hours.

MAKE THE CAKE. Preheat the oven to 180°C (350°F/Gas 4) and butter a 20 cm (8 inches) square cake tin with sides. Work the butter with the sugar in a mixing bowl using an electric beater, then add the eggs, milk, flour, cocoa and baking powder. Beat until the mixture is uniform.

POUR THE BATTER INTO THE BUTTERED TIN AND BAKE FOR ABOUT 25 MINUTES. To check whether the cake is done, insert the blade of a knife into the middle; it should come out clean. Once it is out of the oven, let the cake cool for a few minutes before turning it out to cool completely.

ONCE THE CAKE IS COOL, CUT IT IN HALF HORIZONTALLY. Take the ice cream out of the freezer and spread it on one of the cake halves. Place the second half on top and press down to fully enclose the ice cream. Wrap the cake in plastic wrap and place it in the freezer to firm it up well.

MEANWHILE, MAKE THE SAUCE. Break the chocolate into pieces and dice the butter. Put them in a mixing bowl. Bring the cream to the boil in a saucepan, then pour it over the chocolate and butter. Wait 1–2 minutes for the chocolate and butter to melt, then stir everything together.

BEFORE SERVING, DUST THE CAKE WITH ICING SUGAR AND COCOA IF YOU LIKE, CUT INTO THIN SLICES AND POUR OVER A LITTLE WARM CHOCOLATE SAUCE.