The crust is made of muerbeteig, a rich, crumbly dough that is often used to make cookies.

FOR THE MUERBETEIG:

1 lemon
1 1/2 sticks cold unsalted butter
2 c. flour
1/3 c. sugar
2 egg yolks

TO FINISH:

12 to 14 ripe plums
6 tbsp. sugar
2 tsp. ground cinnamon
3 tbsp. butter, cut in sm. pieces
1 c. heavy cream, beaten to soft peaks (optional)

Prepare the dough. Finely grate the lemon zest. Squeeze the lemon juice. Cut the butter into the flour and sugar, using a food processor fitted with a chopping blade or a pastry cutter or two knives in a bowl. Continue cutting until mixture feels like sand.

Add the lemon zest, lemon juice and egg yolks. Mix until the ingredients come together into a rough dough. Press the dough into the bottom and sides of a 12 inch tart pan with a removable bottom.

Wash, halve, and pit the plums. Mix the sugar and cinnamon. Sprinkle half the sugar mixture over the dough. Press the fruit into the dough, cut side down, in concentric circles. The plums should be firmly embedded in the crust. Sprinkle the remaining cinnamon sugar over the plums and dot with butter.

Bake the plum kuchen at 375 degrees for 40 minutes, or until the top is browned and the fruit is soft and bubbling. Gently remove the rim of the tart pan. Serve plum kuchen warm or at room temperature, with unsweetened whipped cream on the side.