In a separate bowl, mix flour with baking powder and salt.
Add the shredded cheeses.
Add the dry ingredients.
Mix until well combined, approximately 7 min.
Add the shredded zucchini to the egg mixture.
Can use an electric mixer or mix by hand with a wooden spoon.
Should be a runnier texture, not a typical dough consistency.
Can pour or scoop the mixture into the pan and level. Pour into a greased 9x13 glass pan.
Bake at 420F for 15 minutes.
Remove the baking pan from the oven and add the toppings.
Cover the crust with a thin layer of sauce, then add olives, mushrooms and top with remaining mozzarella cheese.
Bake for another 10 minutes.
Remove and serve hot.