Crumble the yeast into a small bowl. Sprinkle 15 g sugar over it. Mix flour, 35 g sugar, salt and 85 g sugar crystals. Melt butter and add cold milk. Pour lukewarm fat-milk mixture over the flour.
Mix yeast and sugar until the yeast has dissolved. Pour over the flour. Knead to a smooth dough with the dough hooks of the hand mixer. Cover and leave to rise in a warm place for about 30 minutes. Knead well with your hands again. Pour into a greased springform pan (20 cm Ø, 7.5 cm high) sprinkled with flour, cover and leave to rise again in a warm place for 30-40 minutes. Whisk egg yolk and cream. Spread the yeast dough with it and sprinkle with 15 g of sugar crystals. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 45 minutes. If necessary, cover the yeast after about 25 minutes of baking time.
Pour into a greased springform pan (20 cm Ø, 7.5 cm high) sprinkled with flour, cover and leave to rise again in a warm place for 30-40 minutes. Whisk egg yolk and cream. Spread the yeast dough with it and sprinkle with 15 g of sugar crystals. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 45 minutes. If necessary, cover the yeast after about 25 minutes of baking time. Remove from the oven, place on a rack, let cool, remove from the mould and serve on a plate. Jam tastes good with it