Pumpkin shortbread dessert

In a bowl,combine 1/4 cup sugar and flour,cut in butter until the mixture resembles coarse crumbs. Press into an ungreased 13x9x2-inch baking pan. In a bowl, combine the eggs,pumpkin,salt spices and remaining sugar. Stir in milk. Pour over crust Bake @ 425 for 15 minutes. Reduce heat to 350 degrees,bake 50 to 55 minutes longer or until filling is set. Cool on a wire rack. Cover and refrigerate overnight. Cut into squares. Top with whipped cream and sprinkle with cinnamon if desired.