Preheat an oven to 180°C.
In a mixing bowl, beat the eggs and sugar together until light and fluffy. Add the flour and vanilla essence and beat into a thick batter. Pour into a lined slice-tin and bake for 10-12 minutes.
Remove from the oven and place onto a large piece of greaseproof paper sprinkled with icing sugar. Spread the whole cake with the boysenberry jam and roll it up tightly.
To serve – slice a piece of cake and plate with fresh berries, cream and a sprinkle of icing sugar.
½ cup caster sugar
¾ cup self-raising flour
1 teaspoon vanilla essence
1 jar Montrose boysenberry jam