01 -  Whisk eggs, milk, salt, and black pepper in a mixing bowl until thoroughly blended. 
 02 -  Place a 10-inch non-stick skillet over medium heat and coat evenly with unsalted butter. 
 03 -  Add minced garlic and sauté for 30 seconds until aromatic but not browned. 
 04 -  Pour the egg mixture into the skillet and cook gently, stirring with a spatula, until eggs start to set but remain slightly soft on top, about 2 minutes. 
 05 -  Evenly sprinkle cheddar and mozzarella cheeses over the eggs; scatter parsley if desired. 
 06 -  Lay the flour tortilla directly onto the egg-cheese mixture, pressing lightly with a spatula. Continue cooking 1 to 2 minutes until eggs are almost fully set. 
 07 -  Use a large spatula, or invert the pan onto a plate then slide back into the skillet, to flip so the tortilla is now on the bottom. 
 08 -  Cook for 1 to 2 minutes until the tortilla is crispy and golden. 
 09 -  Transfer to a plate, fold in half, slice, and serve immediately while hot.