Roasted Hazelnut Buns

For the cupcakes: heat the oven to 180°C (160° fan) 350°F gas 4. Grease 15 muffin tins.

Sift the flour, baking powder and salt into a bowl. Stir in the hazelnuts and set aside.

Beat together the butter and both sugars in a mixing bowl until smooth. Beat in the vanilla.

Add the flour mixture in 3 batches, alternating with 2 additions of milk, beating well after each.

Whisk the egg whites until soft peaks form. Gradually fold the egg whites into the cake mixture until blended.

Spoon into the tins and bake for about 25 minutes, until a skewer inserted into the centre comes out clean. Cool in the tins for 15 minutes, then place on a wire rack to cool completely.

For the topping: whisk together the egg yolks, sugar and flour until pale and creamy.

Heat the milk to a boil in a pan and pour onto the egg yolk mixture, whisking constantly until smooth. Pour the mixture into the pan and bring to a boil, whisking, then boil gently for 2 minutes, whisking constantly.

Pour into a bowl and stir in half the butter until melted. Set aside to cool.

Whisk in the remaining butter and hazelnut paste until blended.