Preheat oven to 375 degrees F. Lightly spray a 13x9-inch baking dish with nonstick spray.
Cookie Layer: In a large bowl, beat together 1/2 cup sugar and 1/2 cup softened butter with an electric mixer on medium speed. Beat in egg until combined, followed by 1 1/2 cups flour, baking powder, 1/8 teaspoon salt, and zest from half of lemon. Press into thin layer into bottom of prepared pan.
Peach Filling: In a large mixing bowl, combine peaches, 1/2 cup sugar, and juice from one lemon. Pour over crust.
Crumb Topping: In a large mixing bowl, combine 1/2 cup sugar, 1 1/2 cups flour, 1/8 teaspoon salt, and zest from 1/2 lemon. Cut in butter with a pastry blender or two knifes until mixture is crumbly. Sprinkle over peaches.
Bake bars for 45 minutes or until golden brown.
SNAPPY TIPS: If you have a hard time cutting in the butter for the crumb topping, just use your fingers.SNAPPY SUBSTITUTIONS: Substitute your favorite fruit instead of peaches. If you are using fruit such as apples or pears, thinly slice so they can bake through or precook for a few minutes in a pan or in the microwave.