The fluffiest yeast kolaches with quark, poppy seeds and fruit

Ingredients

Yeast dough:

• 250 ml lukewarm milk

• 20–21 g fresh yeast (1/2 cube)

• 500 g plain flour

• 100 g granulated sugar

• 1 tablespoon sugar (for the sponge)

• 1 packet vanilla sugar

• a pinch of salt

• 2 egg yolks

• finely grated zest of 1/2 lemon

• 100 g butter (melted and cooled)

Quark filling:

• 250 g smooth quark

• 1 egg yolk

• 1–2 tablespoons powdered sugar

• 1 packet vanilla sugar

• 1 teaspoon rum (optional)

Poppy-seed filling:

• 150 g ground poppy seeds

• 120 ml milk

• 2–3 tablespoons sugar

• a pinch of lemon zest

Fruit and jam:

• apricots cut into smaller pieces or other seasonal fruit

• currant or plum jam

Streusel:

• 60 g semi-coarse flour

• 40 g sugar

• 40 g cold butter

For brushing after baking:

• 40 g melted butter

• 1 tablespoon rum