Heat oven to 425^. Bake an 8-in pie crust for 8 minutes. Remove from oven and brush bottom with butter; set aside. Turn oven heat down to 350^.
Mix together the mashed peaches ,sugar, cornstarch,and water in a large saucepan and cook on medium heat until mixture begins to boil. Remove from heat and add almond extract and butter.
Place the 2/3 of the sliced peached into the partially baked pie shell. Pour in cooked mixture, and then the remaining peach slices on top and sprinkle with a Tablespoon of sugar and bake in 350^ oven for 15 minutes. Remove from oven and cool on wire rack. Then chill for 3 hours. Serve with whipped cream or ice cream.