Step one is the only time consuming part of this cake. Wash your tangerines and put them in a saucepan covered with cold water. (They'll float, but don't worry about that) Bring to a boil, and boil for a full 15 minutes. The boiling removes the bitterness in the citrus skin.

Drain and let the tangerines cool for a bit. Slice them in half, and then in half again. Remove any seeds and discard, but do this on a plate so you don't lose any juice or pulp. Put it all in a food processor and process until completely smooth. You may have to stop and scrape down the sides a few times. My finished puree weighed 11 1/2 oz, (about a cup) and I highly recommend weighing the puree and only using the 11 1/2 ounces. Too much puree will throw off the balance of ingredients in this cake.

Set aside, or refrigerate until the next day if you want to do this ahead.

The rest is a one bowl deal: Beat the eggs and sugar until light and creamy. Fold in the almond meal, orange pulp, baking powder, and Amaretto, if using. Mix until well combined.

Bake for 50-60 minutes, until lightly golden and a toothpick inserted in the center comes out clean. If the cake is browning too fast, cover loosely with a sheet of foil.

Cool on a rack for 10 minutes, then remove from the pan to finish cooling.

Dust with confectioner's sugar. Decorate with some citrus zest if you like.