VERY thoroughly grease an 8, 9, or 10-inch spring-form pan (baking times will vary depending on pan’s size). Really lather on the butter or shortening to make sure the cake—which is very light and delicate—doesn’t stick. Preheat your oven to 350 degrees.

In a mixer or with a whisk, beat the egg yolks and sugar until pale yellow and smooth. Fold in the lemon and orange zest and the ground almonds. With a clean whisk or beaters, beat the egg whites until they form stiff peaks. With a spatula, gently and thoroughly fold the egg whites into the batter. Pour into the prepared pan and bake for 45 minutes to an hour. Cool for 30 minutes before carefully removing from the pan.

While the cake is cooling, put the chopped chocolate into a heat-safe bowl. Heat the cream until it just comes to a simmer, and pour the cream into the bowl with the chocolate. Let stand for 2 minutes and then stir it all together until smooth and glassy. Allow the chocolate to cool in the fridge for 15 minutes and pour it over the top of the cooled cake. Sprinkle with sea salt and more ground almonds if desired. Serve!