Start by adding into a large bowl the warm water, the warm milk, the dry yeast powder and the sugar, mix very well.
Add the eggs, the oil, the salt, the black pepper and the dried parsley, mix very well again.
Now gradually add the wheat flour and the baking powder, mix again until combined.
Cover the bowl with plastic wrap and let batter rest for 25 minutes.
After this indicate time, transfer half of this batter to a baking dish greased with butter and flour. I’m using a 30cm x 20cm baking dish. Evenly spread the batter all over the bottom.
Add the diced mozzarella cheese, add the diced American cheese and finally, the diced buffalo mozzarella cheese.
Add the diced sausage and the chopped olives, then pour the rest of the batter all over it, spreading very well.
Top it with oregano to taste.
Take it to a preheated oven at 190°C (374°F) for 40 minutes
Serve.