Preheat oven to 425° F. Line a sheet tray with parchment paper and set aside. Make the filling: Mix the peaches and strawberries together in a medium bowl. Add the sugar, lemon extract and lemon zest and toss to coat well. Set aside and allow the mixture to sit. On a lightly floured surface, take pie crust and roll dough into a 12-inch circle. Transfer dough to prepared baking sheet. Using a slotted spoon, spoon the fruit into the center of the dough, leave a 2-3 inch border all around the fruit. Fold the edges of the dough over the fruit, overlapping the dough as necessary. Press gently to seal the edges. Pour 1-2 tablespoons of reserved juice over the fruit (too much juice will make the dough soggy). Brush the crust with beaten egg and sprinkle with raw sugar. Bake for 25-35 minutes or until crust is golden brown. Remove from oven and allow to slightly cool before serving. Watch the video on how to make a strawberry peach galette here.