This is a light, refreshing cake, ideal after a heavy meal or in the middle of the summer when a heavier dessert is just too much. It is particularly delicious served with a scoop of fresh blueberries or raspberries and garnished with a sprig of mint.
Prepare the ring mold or loaf pans by spraying with a vegetable oil spray. With a carrot peeler, remove just the yellow portion of the peel from 2 whole lemons. Cut this peel into 2" pieces, and add it to the work bowl of a food processor fitted with the metal blade. Add the granulated sugar, and combine by pulsing the processor on and off 5 or 6 times. Process until the peel is finely chopped (60 seconds). The sugar will be lightly colored with lemon but have no large pieces of peel. Add shortening or butter, and process until smooth (30 seconds). Add eggs and process 30 seconds. With a rubber spatula, scrape the sides of the work bowl. Stir the flour and baking powder together in a mixing bowl, and add to the work bowl. Pulse on and off, just until the flour disappears. Do not over process or the cake will be dry. Transfer the batter to the prepared pan or pans. Swirl the pan(s) back and forth on the counter a few times to release any trapped air bubbles. Bake in the preheated oven for 50-55 minutes until a toothpick inserted near the center comes out clean. Let cool slightly in pan. Mix confectioners' sugar and juice. Reverse the cake on a wire cooling rack, and place this over a piece of waxed paper or foil. With a pastry brush, glaze the cake until all the glaze is absorbed. Cool cake thoroughly, and wrap tightly.
Lemon cake freezes well for about 2 months. As with all baked goods, be sure to double-wrap it, and try to store in a NON-frost free freezer. Then thaw at room temperature in the freezer wrapping, and dispose of the wrapping as soon as it is defrosted. Rewrap in fresh plastic until you are ready to eat it.