Chocolate and Hazelnut Roulade

• Heat oven to 190C/fan170C/ gas 5. To make the sponge, line the base and sides of a 30 cm x 40cm swiss roll tin with a sheet of buttered baking paper Dust with 1 tbsp plain flour and tip out the excess. Sift the flour, baking powder, and cocoa onto a plate and mix in50 grams of ground hazelnuts.
• Beat the eggs and sugar in a stand mixer with a whisk beater and mix until the mixture is pale and trebled in volume. Add the dry ingredients and fold in carefully using a large metal spoon. Spoon into the prepared tin and spread level, being careful not to knock out any air. Bake for 10-12 minutes or until firm to the touch. Cool for 1 minute.
• Lay a large piece of baking paper on the bench and scatter with the remaining hazelnuts and 1 tbsp caster sugar. Turn the sponge out onto the baking paper. Peel off the bottom baking paper and roll the roulade up with the other sheet of baking paper. Leave until cold.

Filling

• Melt the chocolate then cool slightly. Beat the egg yolks and caster sugar until pale and thick. Softly whip the cream. Fold the chocolate into the egg mixture. Add the whipped cream and mix gently.
• Unroll the roulade and spread with the filling. Spread the filling on top of the chocolate filling. Make sure to leave a 1cm border all around the edges. Roll the sponge back up and away from you as tightly as possible. dust with icing sugar and cut into slices.