Brennan's Vanilla Ice cream is a must for this pie. You can make this pie 1 day ahead and keep at room temperature.
Place a baking sheet in the middle of the oven and preheat to 450F. Whisk together cornstarch, salt and 1 cup plus 2 tablespoons sugar in a large bowl.
Prepare your crust recipe. Divide in half. Roll out each piece large enough to fit into to 9-inch pan. Top piece should be 11-inch round. Press the dough over the bottom and sides of the pan. Trim the edges to about 1/2-inch.
Stir apricots into sugar mixture until combined, then gently stir in raspberries and spoon filling into shell. Lay reserved dough over the fruit. Trim, and crimp the edges. Brush top of pie with egg and sprinkle all over with remaining sugar. Cut 3 steam vents in top crust with a small sharp knife. Put the pie on a baking sheet for 15 minutes. Reduce oven temperature to 375F and continue to bake until crust is golden brown and filling is bubbling, about 45 minutes more. Cool on rack at least 2 hours before serving.