How To: Bake a vegan sponge cake

You won't believe its vegan, a creamy rich sponge cake that everyone will love.
Serves: 12 approx
Preparation: 20 mins
Type: Vegan, Vegetarian, Halal, Kosher pareve passover.
Cooking time: 45 mins
Ingredients: 6 tbsp potato starch, 175g self raising flour, 175g vegetable margarine, 175g white vegan sugar, ¾ cup water/soya milk, 2-3 tbsp jam, Extra margarine and flour for greasing