In a large bowl, add the water, milk, sugar and fresh yeast and mix well. Let sit for five minutes.
Now add the flour, salt, egg and butter. Knead the ingredients until you have a smooth dough. Cover and set the dough in a warm place to rise for one hour.
Sprinkle flour on your work surface and form your dough into a large sphere. Now, cut it into four equal parts.
Place the pieces of dough onto a baking sheet lined with baking paper. Press flat until they are about 3.5 inches in diameter. Don't place them too close to one another, because the dough will continue to grow. Once again, let the dough sit for an hour on the baking sheet.
Afterwards, mix the second egg with the milk and water. Brush the mixture onto the dough and then sprinkle with sesame seeds.
Now bake the hamburger buns for 15-20 minutes at 390° F. Tip: Warm up a bit of butter in a pan and toast your finished, sliced hamburger buns. This will leave them irresistibly crispy and even more delicious.
