German Cheese Cake

Instructions

1. Prepare the crust
   In a large bowl, combine flour, 1/2 cup sugar, and baking powder. Add the cold, cubed butter and work it into the dry ingredients using your fingertips until the mixture resembles coarse crumbs. Add 1 egg and mix until a dough forms. Wrap in plastic and refrigerate for 30 minutes.
2. Preheat the oven
   Preheat your oven to 350°F (175°C). Grease a 9-inch springform pan.
3. Form the crust
   Roll out about 2/3 of the dough on a floured surface and line the bottom and sides of the springform pan. Use a fork to prick the bottom several times. Reserve the remaining dough for decoration if desired.
4. Prepare the filling
   In a large bowl, beat the quark or cottage cheese until smooth. Add 1 cup sugar, egg yolks, cornstarch, vanilla extract, lemon zest, and lemon juice. Mix until well combined. In a separate bowl, whip the heavy cream until stiff peaks form and fold it into the cheese mixture.
5. Beat the egg whites
   In another clean bowl, beat the egg whites until stiff peaks form. Gently fold the beaten egg whites into the cheese mixture, being careful not to deflate the mixture too much.
6. Assemble and bake
   Pour the filling into the prepared crust. If desired, roll out the remaining dough and cut into strips to create a lattice pattern on top of the cake. Bake for 1 hour to 1 hour 15 minutes, or until the center is set but still slightly jiggly and the top is golden brown.
7. Cool properly
   Turn off the oven and leave the cake inside with the door slightly open for 15 minutes. This helps prevent the cake from cracking. Then remove from the oven and let cool completely at room temperature before removing from the springform pan.