For the crust
2 cups (250 g) all-purpose flour, plus extra for ousting
9 Tbsp. (125 g) unsalted butter, cubed, plus extra for greasing
⅓ cup superfine sugar
2 tsp. vanilla sugar
Zest of 1 lemon
1 medium egg
Pinch salt
Egg yolk, for glazing
For the topping
About 2 pounds (1 kg.) plums
⅓ cups (75 g) all-purpose flour
½ cup (50 g) ground almonds
½ cup (100 g) granulated sugar
6½ Tbsp. (100 g) unsalted butter, cubed
½ tsp. ground cinnamon

Step 1
Preheat the oven to 375°F. Grease and line a 10-inch springform cake pan with parchment paper.

Step 2
Put all the ingredients for the crust, except the egg yolk, into a bowl. With your hands, mix and work the ingredients together until the dough becomes smooth and pliable. On a floured surface, roll out the dough slightly larger than the diameter of the pan. Transfer the dough to the pan—there should be a rim of about 1 inch around the sides. Brush the inside of the crust with egg yolk.

Step 3
Prepare the plums. Wash them, halve them, and remove the pits. Then, from the cut side, cut them again about halfway through. Arrange the plums on the crust.

Step 4
For the streusel, add the remaining topping ingredients to a separate bowl and mix, working it with your hands until it holds together in big chunks. Spread the chunks randomly over the plums, leaving part of the plums uncovered.

Step 5
Bake for about 70 minutes. Keep an eye on the color of the streusel and don’t let it get too dark.

Step 6
This cake tastes great warm, and whipped cream or vanilla ice cream are good accompaniments. It keeps well for several days, stored in an airtight container.