8 peaches, peeled and sliced (6 to 8 cups)
1/4 cup bourbon
3/4 cup sugar, plus more for sprinkling
2 tablespoons cornstarch
1 teaspoon ground cinnamon, plus more for sprinkling
1 1/2 cups all-purpose flour
2 teaspoons baking powder
1/2 teaspoon kosher salt
2 sticks cold unsalted butter
3/4 cup heavy cream, plus more for brushing
1 quart vanilla-bean ice cream, for serving