Zwetschekuchen (German Plum Tart)

Place the flour, 1 1/3 cup of sugar, lemon peel, cinnamon, and butter into the work bowl of a food processor, and process until the mixture turns grainy. Stop the machine, add eggs and egg yolks, and process in the machine until the mixture gathers itself up into one dough ball. If the dough doesn't ball up, stop the machine, sprinkle several drops of water onto the dough, and process again. Place the dough into a covered container and refrigerate at least 3 hours or preferably overnight.

The next day, preheat oven to 350 degrees F (175 degrees C). Allow the dough to rest at room temperature for about 30 minutes to warm up.

Roll out the dough on a well-floured surface to make a 9 1/2-inch circle. Dough will be rich and sticky. Scrape up the dough circle, and press into a 9-inch pie dish. Quarter and slice the plums, and place skin sides down onto the dough in a neat ring, starting at the outer edge and working in a neat row towards the center.

Bake in the preheated oven until the plums are bubbling hot and the crust starts to brown, about 45 minutes.

Allow the tart to cool, and sprinkle with 1 tablespoon of sugar before serving.