Preheat oven to 350°F. For crust, combine 1 cup flour, 1/4 cup sugar, butter and 1 tablespoon tangerine peel in small mixer bowl. Beat with electric mixer at low speed 1 to 2 mintues until coarse crumbs form. Press on bottom of 9-inch square baking pan. Bake 10 to 12 minutes or until edges are lightly browned.
For filling, combine 1/2 cup sugar, coconut, eggs, 2 tablespoons flour, baking powder, salt, 1-1/2 tablespoons tangerine peel, eggs, orange juice and liqueur in small mixer bowl. Beat at medium speed 1 to 2 minutes until well blended. Pour over hot crust. Bake 20 to 25 minutes or until edges are lightly browned. Immediately sprinkle with orange peel, if desired. Cool completely. Cut into bars.