Cream together the butter and sugar.
220 g butter, 220 g caster sugar (superfine sugar)
Add the eggs one by one, and mix well after adding each one.
4 eggs
Fold in the flour, ground almonds, baking powder and vanilla extract and mix until just combined.
50 g ground almonds, 170 g self raising flour, 1 tsp baking powder, 1 tsp vanilla extract
Grease the pan, pour in the cake batter and smooth around the dish with a spatula.
Spread the blackcurrants over the top.
300 g blackcurrants
Bake for 35-40 minutes at 180 degrees in a preheated oven, or until the sponge is golden brown and the centre of the cake is firm and a skewer comes out clean.
Allow to cool in the dish, sprinkle with icing sugar, then cut into squares to serve.
icing sugar