To make the sponge pudding, grease a pudding basin with butter then dust with self-raising flour.
Place the flour, sugar, butter and baking powder into a food processor and blend. While blending add the eggs and continue blending until a thick batter is formed.
Meanwhile, place the honey and grapes into the base of the pudding basin. Add the sponge batter and cover with cling film.
Place into the microwave and cook on full power for five minutes, or until cooked and risen.
To make the custard, mix the yolks and sugar together in a large bowl.
Place the cream, the vanilla pod and seeds into a saucepan over a medium heat. Bring the cream to just boiling, then remove from the heat and cool for one minute. Remove the vanilla pod.
Gradually pour the warm vanilla cream into the yolk mixture, whilst whisking continuously and vigorously.
Pour this mixture back into the saucepan and gently heat, stirring continuously. When the custard reaches a consistency that coats the back of a wooden spoon it is ready.
To serve, turn the sponge out onto a warm serving plate and pour over some of the custard.