About this recipe:A great stand-by dessert. I use it over and over again. I've suggested apples and blackberries in this recipe, but I've done it with all sorts of things like raspberries, strawberries, blueberries, rhubarb, pears, mango, orange, tinned peaches. Just adjust the cooking of the fruit to suit your chosen fruit or preference. I've cooked the apples and blackberries but wouldn't bother with tropical fruits for example.
Preheat the oven to 180 C / Gas 4. Grease a small cake tin and line with baking parchment (it doesn't really matter what shape it is as the sponge will be torn up when you use it, even a loaf tin will do).
Weigh the egg and record on a piece of paper. Weigh the same amounts of margarine, sugar and flour. In a mixing bowl, combine the sugar and butter and beat together with an electric mixer or a wooden spoon until soft and fluffy. Add the egg and vanilla extract and continue beating until the mixture is fairly smooth. Gradually sift in the flour and beat until well combined. Transfer to the prepared cake tin.
Bake in the preheated oven for 15 to 20 minutes or until a skewer inserted in the centre comes out clean. Remove from the oven and allow to cool in the tin for 10 minutes then remove from the tin and allow to completely on a cooling rack, about 1 hour.
For the layers:
In a saucepan over a medium heat, cook the apples and blackberries with a bit of sugar until soft, but holding their shape, about 5 to 8 minutes. Remove from the heat and allow to cool.
Pour the cream into a mixing bowl and whisk using a handheld whisk until soft peaks form. Whip enough cream to cover the top of whatever serving dish you're going to put the trifle in. I've done it in a big glass bowl, individual wine glasses, cups or cleaned out jars all good.
Once the sponge is cooled you can start constructing. Tear or cut the sponge into appropriately sized pieces depending on your serving dish(es) and line the bottom(s). Press it down a bit so it fills the bottom of the bowl. Add a layer of the fruit including a bit of the juice released when cooking. Pour the custard over the fruit so that you can't see any fruit through the top of the custard and leave it to set in the fridge for at least 30 minutes.
Remove from the fridge and spoon or pipe the whipped cream on top. Decorate with sprinkles or chocolate shavings and serve.