Add flour, sugar, baking powder, cinnamon, nutmeg, and salt to a food processor and mix shortly to combine all ingredients.
Add butter and pulse until the mixture resembles wet sand.
Add the liquid (water, milk, and/or egg yolks) one tablespoon at a time and vanilla extract (or seeds). Pulse until the pastry comes together.
Wrap the pastry in a plastic foil and place it in the fridge for 30 minutes.
In the meantime, cut plums in half (or into quarters for larger plums).
After 30 minutes divide the dough into 1/3 and 2/3. Use the bigger piece to roll out the bottom of the pie. I only cover the bottom, but you can cover the sides as well, only the crust will be a bit thinner.
Place plums on top so they cover the entire surface.
Use the remaining 1/3 of the pastry to decorate the top.
Sprinkle with a tablespoon or two of sugar.
Bake in a preheated oven at 180°C (355°F) for 55-60 minutes.
Recipe by Anja Burgar | Use your Noodles | www.useyournoodles.eu