Grease and line two 8inch/20cm sandwich tins and preheat your oven to 350F/180C/Gas 4.
Cream the butter or margerine with the sugar until soft and light. Beat in the eggs one by one, adding 1 tbsp flour with each. Fold in the rest of the flour and baking powder, if used.
Spoon the mixture evenly into both tins, smoothing the tops. Place in the oven for 18-20 mins, or until no impression is left when you press the centre of the sponges gently but firmly. Allow to cool in the tins for 2 mins then turn out on to a wire rack.
When the cakes are cold, spoon 3/4 of the double cream on top of one cake and the majority of the strawberries. Place the other cake on top, putting the rest of the cream on top along with the remaining strawberries and serve.
If you're in a hurry shove all the ingredients for the cake in a bowl and cream together. Bake as above then fill.