In a small bowl, add the water, milk, yeast and sugar together and mix until yeast is dissolved.

In a large bowl, mix the flours, salt and butter together. Using a food processor (or a pastry cutter), cut the butter into the flour until coarse crumbs form.

Dig a well in the middle the flour and slowly add the yeast mixture. Mix well using dough hook or with your hands.

Turn the dough on a lightly floured surface and knead the dough for about 5 minutes. The dough should still be a little sticky, but fairly easy to manage.

Put the dough in a lightly oiled bowl and cover with plastic (Note: Lightly grease the plastic so the dough doesn't stick to it). Allow it to rise for about 30 - 45 minutes.

Deflate the dough by gently punching it down. Break the dough into about 8 equal chunks. Roll out each piece of dough and form a bun. I do this by rolling it into a ball and slowly shaping it with my hands.

Place the buns on a pan lined with parchment paper and allow them to rise again for another 15 - 20 minutes.

While the dough is rising, preheat the oven to 400 degrees and make your egg wash by beating one egg with a tablespoon of water. Place an empty heat-resistant baking pan at the bottom of the oven.

Lightly brush the tops of the buns with the egg wash and top with your desired toppings.

Open the oven and put 1 cup of water in the baking pan at the bottom of your oven. Place your burger buns in the oven and let them bake for 15 - 20 minutes, or until the tops are a nice golden brown.