In a medium bowl, stir together graham cracker crumbs and sugar. Stir in the melted butter until the crumbs are moistened. Remove 1/3 C. of the crumbs and set aside for later.
Press the remaining crumb mixture on the bottom of a 9X13-inch pan. Refrigerate.
In a large bowl using an electric handheld mixer or in the bowl of an electric stand mixer, mix the powdered sugar and cream cheese together until light and smooth, 1-2 minutes. Mix in the vanilla.
Pour in the cold heavy cream and mix on low until the mixture starts to come together. Increase the speed to medium-high and mix until the mixture is thick and fluffy.
Spread half of the cream filling over the chilled crust. Layer the sliced peaches over the top of the cream.
Scoop the remaining cream over the top of the peaches in large spoonfuls. Spread carefully to the edges of the pan to cover the peaches completely.
Sprinkle reserved graham cracker crumbs over the top. Cover with plastic wrap and chill for at least 2 hours before serving.
Notes
My friend, Laura Dibble made this for us for a dinner party. It is scrumdillyumptios!! It's wonderful during peach season!