Preheat oven to 400ºF. Cut peaches in half and remove pits. Cut each peach half into four slices. Combine peaches, sugar, lemon juice, cinnamon and cornstarch in a medium bowl; set aside.
Melt butter in microwave or on stovetop. Crush gingersnaps into crumbs; place in a small bowl. Pour melted butter into crumbs and combine thoroughly. Pat crumb mixture into bottom of a 9-inch ceramic or glass pie plate; make sure crumbs are evenly distributed.
Starting at edge of pie plate, arrange peach slices in concentric circles so that they cover entire surface of pie and form a petal-like pattern. To form center of ‘flower,’ arrange several peach slices into a small circle. Pour any remaining liquid from peach mixture over top of pie so it is evenly distributed.
Bake pie in bottom third of oven for 20 minutes; reduce heat to 325ºF and bake for 40 minutes more. Remove from oven and cool completely in pie plate on a wire rack (about 2 hours). Slice into 8 pieces just before serving.