Preheat oven to 160°C.
Cream the butter and sugar together until light and fluffy.
Add the eggs one at a time, beating well after each addition.
Fold in the flour and baking powder until just combined.
Pour the batter into two fully lined 8 inch cake tins.
Bake for 30-35 minutes until a toothpick inserted comes out clean.
Allow the cakes to cool completely.
Whip the cream with the icing sugar and 1tsp vanilla essence.
Spread the jam onto one cake layer, then top with the whipped cream.
Place the other cake layer on top and dust with icing sugar.
