Wash, clean and quarter the strawberries and sprinkle with 2 tablespoons of sugar. Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Grease casserole dish
Separate eggs. Mix egg yolks with quark, 125 g sugar, vanilla sugar, 1 pinch of salt and semolina. Fold about half the strawberries into the quark mixture. Beat the egg white until stiff, fold in 2 portions. Pour the mixture into the mould. Bake in a hot oven for 50-60 minutes.
Remove from the oven and dust with icing sugar. Serve the casserole with the remaining strawberries.