Stir yeast with sugar until liquid. Heat the fat and milk. Add 60 ml water and cool down lukewarm. Put 1/2 tsp salt, flour and egg in a bowl. Add milk mixture and immediately knead into an elastic dough with the dough hooks of the hand mixer for 6-8 minutes.
Cover and leave to rise in a warm place for about 45 minutes.
Knead the dough again briefly on a floured work surface. Form approx. 24 small round rolls from the dough. Put them on two baking trays lined with baking paper, cover and let them rise for another 20 minutes.
Whisk the egg yolk and cream. Spread the bread roll with it, sprinkle with sesame seeds. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) one after the other for 15-18 minutes.
Take out and let cool on a cake rack.