I think that many of you do the filling. I've just mixed the fruit with cornstarch, but the result was not satisfied. Fruit juice still flowed and burn. Then decided to boil the fruit with starch and was satisfied. So since doing any fruit. It is very convenient. The filling is thermostable and remains not flowing. The amount of sugar in the recipe how to add and subtract. The same applies to the amount of starch. It all depends on the fruit juiciness and their sweetness. I love that the filling was more plump.