This is a neat trick for freezing fruit so it is ready to go directly into a pie crust for baking. I especially like this for apricots and peaches, but any fresh fruit or berry can be used.
For one pie, combine 4 cups of prepared fruit with 1/2 teaspoon ascorbic acid powder, 3/4 cup sugar (or whatever amount suits your taste), 2 to 3 tablespoons quick cooking tapioca and 2 tablespoons lemon juice. Add a little salt too if that is your usual practice. Gently stir these together, until the fruit is coated with the sugar mixture.
Line an 8" pie pan with heavy duty aluminum foil or several thicknesses of transparent plastic wrap. (Let the lining extend at least 5" beyond the rim of the pan.) Spoon in the fruit and cover loosely with the extended lining. Freeze until firm. Seal the lining tightly over the filling, remove the "package" from the pan and return to the freezer. (This prevents having all your pie pans in the freezer.)
To use, remove the wrapping and set the frozen block of filling into a pastry lined 8" pie pan. (Do not thaw.) Dot filling with 1 tablespoon butter if desired. Add top crust as usual. Bake at 425 degrees (400 degrees in glass pie dishes) until syrup bubbles up through slits, about 1 hour.