Khachapuri (хачапури) is a traditional Georgian dish of cheese-filled bread. It is look like bread boat with a lot of cheese and egg in the middle. There is many kinds of Khachapuri in Georgia but the Adjarian/Acharuli is defiantly the most unique. If you not familiar with this delicious dish now it's the time to try.
in a mixing bowl combine flour, yeast and sugar. Add water, milk and melted butter and start kneading the dough (you can do it also by hand), when dough is formed add salt and knead 6-8 minutes. Transfer the dough into oiled bowl, cover and let rise for 1 hour.
Make the cheese mixture: in a medium bowl put mozzarella, feta cheese and 2 eggs. Mix well.
Remove the dough from the bowl and place it onto a floured surface. Cut the dough into 4-6 equal pieces (depends on the size you want). Shape into balls and cover for 20-30 minutes more.
Preheat oven to 430F (220C).
Roll each dough into 1/8-inch (1/3cm) thick. Shape a boat from the dough and transfer to a parchment paper. Spread equal portions of cheese mixture. Or make the boat in other method: spread the cheese mixture over the rolled dough, close the dough completely by pinching in the middle to close the dough. Flip the khachapuri and cut in the middle with a knife. Open with your fingers.
Bake for 10 minutes, after 10 minutes put an egg yolk with a little of egg white (not a whole egg) in the middle, brush the crust with melted butter and bake 2-3 minutes more.
When the khachapuri is ready you can add 1 cube of butter to the middle, mix it with piece of crust and eat it this way.
Traditionally khachapuri made with suluguni cheese. If you can find it, use this cheese. mozzarella is a good substitute.