For the filling
Preheat the oven to 200°C/400°F/Gas mark 6. Line a 38 x 25cm/ 15 x 10in Swiss roll tin with greaseproof paper.
In a small saucepan over a medium heat, melt the chocolate in 2 tablespoons water, stirring constantly. Leave to cool slightly.
Put the eggs and sugar in a bowl, and whisk for 10 minutes or until the mixture is pale and foamy. Whisk in the chocolate in a thin stream. Sift the flour and cocoa together, and fold into the mixture. Pour into the tin and level the top.
Bake in the oven for 12 minutes. Dust a sheet of greaseproof paper with a little icing sugar, turn the roulade onto it and peel off the lining parchment. Roll up the roulade with the fresh paper inside. Put on a wire rack, cover with a damp tea towel and leave to cool.
To finish, unroll the roulade and spread with the cream. Scatter with the strawberries and re-roll. Put on a plate and dust with icing sugar. Serve cut into slices.