Preheat your oven to a hot 425°F to achieve a beautifully crisp crust.

Roll out your pie crust and fit it snugly into a 9-inch pie plate.

In a small bowl, combine the cornstarch and sugar, mixing well.

In a larger bowl, toss together the raspberries and peaches with the lemon juice and vanilla. Sprinkle the cornstarch mixture over the fruit and toss gently to coat.

Carefully cover the fruity filling with the top crust, sealing the edges well. Cut some slits in the top to let steam escape, brush with an egg wash, and dust with sanding sugar.

Place the pie on a baking sheet to catch any drips. Bake at 425°F for 10 minutes, then lower the temperature to 350°F and continue baking for 45-55 minutes until golden.

Allow the pie to cool completely on a rack before slicing. You can refrigerate it for up to 3 days or freeze it for up to 3 months.