Step 1: Preheat your oven to 350°F (175°C).
Step 2: In a mixing bowl, combine 1 1/2 cups of all-purpose flour and 1/2 cup of confectioners' sugar. Cut in the 3/4 cup of cold butter or margarine until the mixture resembles coarse crumbs. Press this mixture into the bottom of your greased 9x13 inch baking pan. Bake for 15 minutes or until lightly golden.
Step 3: In another bowl, whisk together 4 eggs and gradually mix in 1 1/2 cups of sugar. Add in 1/2 cup of lemon juice and 1 teaspoon of baking powder, whisking until smooth. Finally, fold in 1 cup of flaked coconut.
Step 4: Pour the lemon filling over the pre-baked crust and return to the oven. Bake for an additional 20-25 minutes or until the filling is set and lightly browned on top.
Step 5: Once baked, allow the bars to cool completely in the pan. Cut into squares and dust with extra confectioners' sugar if desired. Enjoy your Lemon Coconut Bars chilled or at room temperature.