German Plum Cake

Instructions

1. Prepare the pan
   Preheat oven to 350°F (175°C). Grease a 9x13-inch baking pan or a 10-inch springform pan and line with parchment paper.
2. Make the dough
   In a large bowl, whisk together flour, sugar, salt, and baking powder. Add cold cubed butter and use a pastry cutter or your fingers to work it into the flour until the mixture resembles coarse crumbs. Add egg and vanilla extract, then mix until the dough comes together. It will be slightly crumbly but should hold together when pressed.
3. Form the base
   Press the dough evenly into the bottom of the prepared pan. If using a springform pan, press the dough about 1 inch up the sides to create a slight edge. Refrigerate for 15 minutes while preparing the plums.
4. Prepare the plums
   Halve and pit the plums. If using larger plums, slice them into quarters. Toss with lemon juice to prevent browning. Arrange the plums cut side up in neat rows on top of the chilled dough, slightly overlapping each piece.
5. Make the streusel
   In a medium bowl, combine flour, sugar, and cinnamon for the streusel topping. Add the cold cubed butter and work it in with your fingers until the mixture forms coarse crumbs of varying sizes.
6. Assemble and bake
   Sprinkle the streusel evenly over the arranged plums. Bake in the preheated oven for 40-45 minutes, or until the crust and streusel are golden brown and the plums are bubbling and soft.
7. Cool and serve
   Allow the cake to cool in the pan for at least 30 minutes. If using a springform pan, carefully remove the sides. Dust with powdered sugar if desired. Serve warm or at room temperature, optionally with a dollop of whipped cream or vanilla ice cream.