Filling Recipe :
(note I had lots of berries cut the recipe in half for less)
1 cup sugar or more if you like sweeter by taste
4 cups raspberries
3 cups blackberries (you can use blueberries also if you want triple berries I would do 3 cups red 2 cups black and 1 cup blue )
3 tablespoons cornstarch
2 tablespoons quick cooking tapioca
1/4 teaspoon each salt and cinnamon
1 tablespoon butter
water if needed
Puree 1 cup berries combined or just the raspberries set aside.
In a medium saucepan add the puree, cornstarch and tapioca. Place on medium heat. When it starts to boil add the sugar until dissolved and starts to thicken it's just a few minutes. Add the salt, cinnamon and butter. Fold in the berries gently. If too thick add a little water.
Use on cakes, cheesecake topping, two crusted pies on ice cream, tarts, cookies, turnovers or anything else you like.