Serve with whipped cream, if you like, and substitute cognac for the vanilla extract. Toasted and skinned hazelnuts can be substituted for the almonds. Use good-quality dark chocolate with a cacao percentage between 60 and 65 percent; our favorites are callebaut intense Dark chocolate, L-60–40nV, and Ghirardelli 60% cacao Bittersweet chocolate. Let tart sit at room temperature before glazing in step 6. Cook time includes chill times.