Crumb the yeast into a dough bowl, a large bowl, or in a mixer.

Add water and salt and dissolve the yeast in it.

Stir in the wheat flour into the yeast liquid until you have a smooth dough.

Add the soft butter in small pieces and mix the dough well.

Now add just enough flour for the dough to become pliable and kneadable. It must absolutely not be dry, but should be slightly moist.

Let the dough rise under a damp cloth - alternatively, you can use a shower cap - for about 30 minutes.

Knock down the dough and shape it into flat buns (see the picture).

Let the buns rise again for 30 minutes.

Break the egg into a deep plate and whisk it with a fork.

Brush the fully risen buns with the beaten egg and sprinkle with sesame seeds.

Bake the buns for 10 minutes at 210 degrees Celsius (410 degrees Fahrenheit), until they are golden and fully baked.

Let the burger buns cool on a baking rack.