Mix flour and butter to a fine crumb; sprinkle evenly in an 11x7" pan. Bake 10 minutes in a 350~F oven. Beat eggs; mix in brown sugar, coconut, chopped nuts, baking powder and vanilla. Spread on the baked mixture when it is removed from oven. Return to oven and bake 20 minutes longer. Mix lemon rind and juice; add confectioners sugar to make a cream mixture. Spread over the top of egg mixture when removed from oven. Cool and cut in squares.
