Raspberry-Rhubarb Pie

The chilled pie dough makes it easier to make this delicious dessert. Corn starch and tapioca add a velvety texture to the filling by thickening the fruit juice. Serve this raspberry and rhubarb pie with whipped cream or vanilla ice cream.
Preheat the oven to 350 degrees.Grind the tapioca in a spice grinder or grind until finely ground. Combine tapioca, raspberries, and the following 5 ingredients (with 1/8 teaspoon salt) in a bowl; mix well. Let the raspberry mixture sit for 10 minutes; stir until smooth.Roll out 1 9-inch-thick portion of dough into an 11-inch-diameter circle. Place the dough on a 9-inch pie dish greased with cooking spray, covering the excess dough around the edges. Spoon the raspberry mixture and remaining liquid into the batter. Bend the edges under the groove. Bake at 350 ° C for 40 minutes.While the cake is baking, put the flour and other ingredients in a food processor; beat 10 times or until the mixture looks like a coarse crumb.Increase the oven temperature to 375 degrees.Sprinkle the cake evenly. Bake at 375 degrees for 15 minutes or until the filling is golden brown and the filling is thick and bubbly. Cool completely on a wire rack.