Wash the oranges and kumquats, and boil them whole in a pot of water for about 1 1/2 hours, or until they are very soft.
Once they’re cool enough to touch, cut them open and remove seeds, and puree in a food processor.
Preheat oven to 325F. In a large bowl, whip egg whites until they form soft peaks.
In another large bowl, combine egg yolks, sugar, orange mixture, orange blossom water, baking powder, and salt.
Add almond meal, and stir to combine.
Gently fold egg whites into batter.
Oil bottom and sides of a 9-inch springform pan, and dust with more almond meal.
Pour batter into pan, and bake for 45 minutes.