Chocolate Truffle Cake

Yield: 12 servings. Melt 150g chocolate in a bowl over a pan of hot water. Cream together butter and sugar until pale and fluffy. Beat in melted chocolate, coffee and egg yolks. Whisk egg yolks until stiff, fold into mixture. Fold in flour and hazelnuts. Pour into a greased and lined 21 cm cake tin. Bake at 170 C / 325 F / Gas 3 for 1 1/4 hours. Cool in the tin for 15 minutes, then on a wire rack. Place cream in a small pan, heat gently until bubbling around the edges. Remove from the heat and stir in remaining chocolate. Allow to stand covered until chocolate melts, mix well then chill until firm enough to hold a peak, approximately 1 1/2 hours. Cover top and sides with icing and swirl with a teaspoon. Decorate with strawberries and leaves.