Take approximately one kilogram of peaches and plums. Cut them in quarters, add a little sugar to them and let them rest to soften and release juices.
After about an hour add cornstarch to the fruit to soak up all the sweet juices, add a little bit more of brown sugar and vanilla sugar, squeezed lemon juice and cinnamon. Combine well and transfert into a pie dish.
Prepare the dough that is going to be used on the upper surface only.
Combine all-purpose flour, sugar, vanilla sugar, salt and baking powder. Mix together all the dry ingredients.
Add butter to them and combine it with your hands until you get a sand-like texture
Now add some buttermilk and prepare the dough. If the dough feels too wet, feel free to add a little more flour.
I always prepare buttermilk by using regular milk and adding a tbsp of vinegar to it. Just let it sit for 5 minutes and its done.
When your dough is ready, spread it over the plums. It is supposed to be messy so dont bother making it flat and perfect. Small holes will let the jammy plum filling bubble out while baking
Coat with some buttermilk and sprinkle with sugar to get that extra crispiness.
Bake in a preheated oven on 180 deg Celsius for 55 to 60 minutes, or when the dough is crispy enough.
Serve warm and dont forget a scoop or two of vanilla ice cream!