A very simple recipe to make. I use the frozen sweet flan bases you get from the supermarket but you could make your own pastry if you wanted to. This recipe can be used with other berries. I think raspberries would be especially delicious. I use the frozen blueberries for this recipe. Dust it with a thin layer of icing sugar, if you want, for presentation. The slight sweetness of the custard balances out nicely with the bitter of the blueberries.