Step one is the only time consuming part of this cake. Wash your tangerines and put them in a saucepan covered with cold water. Boil for 15 minutes. Drain the pan, refill with cold water, and boil again for 15 minutes. This boiling removes the bitterness in the citrus skin.
Rough chop the tangerines and remove any seeds, do this on a plate so you don't lose any juice. Put it all in a food processor and process until completely smooth. You'll have to stop and scrape down the sides a few times. The color and smell will be amazing. My finished puree weighed 11 1/2 oz, and was about a cup.
Set aside, or refrigerate until the next day if you're doing this in 2 stages.
The rest is a one bowl deal- Beat the eggs and sugar until light and creamy. Fold in the almond meal, orange pulp, and baking powder, mixing until combined.
Pour into a buttered 9in. spring form pan.
Bake for 50-60 minutes, until lightly golden and a toothpick inserted in the center comes out clean.