Nutty Chocolate Slices

Put the flour in a heap on a work surface, mix with the sugar and salt and make a well in the centre. Cut the cold butter into small pieces and scatter around the well. Break the egg into the middle, add approximately 30 ml lukewarm water and chop all the ingredients with a knife until they resemble breadcrumbs. Quickly combine to a dough with your hands, then form into a ball, wrap in clingfilm and chill for about 30 minutes.

Roll out the pastry between 2 sheets of baking parchment and use to line a greased tart tin. Chill until the filling is ready.

Chop the butter and chocolate couverture and melt in a bain-marie, stirring.

Separate the eggs, whisk the egg whites until they form stiff peaks and add the lemon juice.

Beat the egg yolks with the sugar, lemon peel and seeds scraped out of the vanilla pod until foamy, then slowly stir in the chocolate mixture.

Place the beaten egg whites on top of the chocolate mixture, sieve the cornflour over and fold in lightly along with the nuts.

Spread the mixture smoothly in the lined tart tin.

Bake in a preheated oven (180°C, bottom shelf) for about 45 minutes.

Meanwhile melt the butter in a frying pan and lightly toast the chopped nuts. Dust with icing sugar and caramelise slightly.

10 minutes before the end of baking time spread the toasted nuts on top of the tart and continue baking until cooked. (Test with a toothpick to see if it is done). When done, take out of the oven, leave to cool slightly in the tin, then remove from the tin and leave to cool completely.