Place the pitted cherries in an ovenproof baking dish or bowl and sprinkle with sugar. Mix the quark, cornstarch, vanilla sugar and egg yolks together. Beat the egg whites until stiff and fold into the quark mixture.
Pour everything over the fruit and bake at 180 ° C for 20 minutes. Serve hot.
Instead of cherries, blueberries, thin apple slices and peach halves also taste very tasty.