Have ready an 8 inch square cake tin which you’ve rubbed with butter and lined with parchment paper.

Preheat the oven to 300 degrees F.

Whisk the egg yolks with the sugar and water until the mixture whitens. Stir in the spread. Melt the butter and pour it into the mixture, then fold in the flour and salt. Beat for a few minutes more. Pour in the milk little by little, beating constantly.

Beat the egg whites until stiff and, using a whisk, gently incorporate them into the batter. Pour the batter into the greased cake tin, smooth the surface with the blade of a knife and bake in the oven for 50 minutes. When the cake comes out of the oven it will wobble slightly. Before turning it out, leave it to set in the fridge for at least 2 hours.

Chef’s Tip: Decorate with a few crushed hazelnuts. You can also make a chocolate icing by mixing 6 oz chocolate hazelnut spread with 8 ½ fluid oz whipping cream. Chill in the fridge for 2 hours then whip until it thickens.