If berries are firm-ripe, use minimum tapioca; if soft-ripe, use the maximum.
6 cups boysenberries or blackberries
1 cup sugar
3 to 4 tablespoons quick-cooking tapioca
1/2 teaspoon ground cinnamon
1/4 teaspoon ground nutmeg
1 tablespoon lemon juice
3 tablespoons blackberry-flavor liqueur (cordial or brandy), optional
Pastry for a double-crust 9-inch pie
Rinse berries and drain dry on absorbent towels. In a large bowl stir together sugar, tapioca, cinnamon, and nutmeg. Add berries, lemon juice, and liqueur; mix gently. Let stand at least 15 minutes or up to 1 hour to soften tapioca, stirring gently now and then, before pouring into pie crust.
Bake over foil in a 400 degree F oven on the lowest rack until pastry is golden brown and filling is bubbly, 55 to 60 minutes.