Unfold piecrusts on a lightly floured surface. Cut leaves from piecrust using leaf-shaped cutters. Mark leaf veins using the tip of a small paring knife. One (15-ounce) package of refrigerated piecrusts will make about 24 (2- to 3-inch) leaves.To make the tinted egg wash, whisk together 3 large eggs and 2 tablespoons water. Pour mixture evenly into small cups, tinting each with a few drops of liquid food coloring to create different colors. (We painted our leaves using four different colors of egg wash--red, yellow, orange, and green. For easy cleanup and to prevent the excess egg wash from burning on the baking sheet, paint leaves on pieces of parchment or wax paper.) Brush leaves evenly with egg wash, beginning with lighter colors first, and overlaying with areas of darker color. Use a small artist's brush to add accents of bolder color with undiluted liquid food coloring. Crumple 2 (14-inch long) pieces of aluminum foil into 1-inch-wide strips. Coat with vegetable cooking spray, and place on a baking sheet lined with parchment paper. Gently drape pastry leaves over the strips of aluminum foil to give them a natural-looking shape; place several leaves on the baking sheet. Bake at 400° for 6 to 8 minutes or until golden. Cool on the baking sheet on a wire rack 10 minutes. Gently remove leaves, and cool completely on a wire rack. Repeat procedure with remaining leaves.