Drain cherries well in a sieve or wash fresh cherries, dab dry and stone them. Grease ovenproof dishes or large casseroles.
Preheat oven (electric cooker: 180 °C/circulating air: 160 °C/gas: see manufacturer). Separate eggs. Beat egg yolks, sugar and vanilla sugar with the whisks of the mixer for about 5 minutes until thick and creamy. Stir in pudding powder and quark with the whisk.
Beat the egg white until stiff and fold loosely into the egg quark mixture.
Pour the curd mixture into the moulds or large mould. Spread the cherries evenly on top. Bake in a hot oven for 45-50 minutes until golden brown. If necessary, cover with aluminium foil after 30 minutes, otherwise your quark casserole will become too brown.
Take out and let cool down briefly. Dust with icing sugar. Mommy's little tip: Vanilla sauce tastes great with it.