Dissolve the yeast in the lukewarm water.
Add all other ingredients to the dough and mix well with a hand mixer or stand mixer until a smooth, slightly sticky dough forms. Leave to rise for 1 hour.
Turn the dough out onto a floured surface, sprinkle some flour on top as well, and roll it out into a rectangle, about 2 cm thick.
Cut out circles of approximately Ø8cm (I used a glass) and use your fingers to make an indentation in each circle.
Put the desired filling into the indentations on your buns.
Let the buns rise again for 30 min.
Brush the buns with a beaten egg and bake them for 15 minutes (200 degrees Celsius (392 degrees Fahrenheit), conventional oven) until they are golden and beautiful.
Let the buns cool, decorate with icing, and serve.