To make Patti LaBelle’s peach cobbler, preheat the oven to 375 degrees Fahrenheit. Peel and pit 3 pounds of medium peaches, and cut them into 1/4-inch slices. Add them to a mixing bowl with 2 tablespoons of cornstarch, 1 cup of sugar, 2 teaspoons of fresh lemon juice and 1/2 teaspoon of ground cinnamon. Toss the peaches to coat them. Transfer half of the peaches to a greased 8-inch square baking pan.
Lightly flour the countertop, and roll out the top portion of a premade double-crust pie dough until it is 1/8-inch thick. Trim the edges to create an 8-inch square to perfectly fit the pan. Lay the dough over the peaches in the pan, and then top the dough with the remaining peaches. Roll out the remaining pie crust dough to a 1/8-inch thickness. Trim the edges so it forms an approximately 11-inch square.
Cover the peaches with the dough, allowing the edges of the dough to lay over the sides of the pan. Gently press the dough against the areas where it touches the pan. Create a few slits in the top of the dough for steam to escape.
Set the baking pan on a flat sheet or pan to catch any dripping fruit juices, and bake the cobbler until the dough is golden brown and crisp, approximately 40 minutes. Garnish it with a sprinkling of cinnamon.