What do you need?
Caramel: 850 g plums, 50 g unsalted butter, 115 g fine granulated sugar, 1 ts lemonjuice
Batter: 100 g unsalted butter, 225 g fine granulated sugar, 4 differentiated eggs, 1 ts vanilla-extract, 155 g flour (no self rising!), 2 ts baking powder, 1 ts ground cinnamon, a pinch of salt
Served with: whipped cream or crème fraîche
Preheat the oven to 180 ° C. Cut the plums in half with a sharp knife and remove their stones.
For the caramel: melt the butter in an ovenproof non-stick frying pan. Add sugar and lemon juice and stir until the sugar is dissolved. Turn up the heat and let the mixture cook for about 5 to 6 minutes until a golden caramel is formed. Put the plums in the pan and cook them gently for 2 minutes.
For the batter: Stir butter and sugar until a light, soft mixture is formed. Add the egg yolks one at a time, and keep beating well after each addition. Add the vanilla, flour, baking powder, cinnamon and salt and whisk until it all becomes smooth. Beat the egg whites stiff in a clean, dry bowl and fold them into the mixture with a metal spoon. Spoon the batter over the plums and smooth the top with a spoon.
Bake the pie 40 minutes. After that, let it stand 1 minute, now you can gently pour the cake upside down onto a large plate. Serve with cream or crème fraîche.