Preheat your oven to 425°F (220°C).
If using pizza dough, roll it out on a floured surface to fit your baking sheet or pizza stone. If using pre-made crust, simply place it on the baking sheet.
In a frying pan over medium heat, cook the crumbled breakfast sausage until browned and fully cooked, about 5-7 minutes. Drain any excess grease and set aside.
In a mixing bowl, whisk together the eggs and milk. Season with salt and pepper to taste.
Pour the egg mixture into the frying pan and cook over medium heat, stirring gently, until the eggs are just set but still soft, about 3-4 minutes. Remove from heat.
Evenly spread the cooked sausage over the pizza crust. Next, add the scrambled eggs on top of the sausage.
Sprinkle the shredded mozzarella and cheddar cheese over the entire pizza, followed by the sliced green onions.
Place the breakfast pizza in the preheated oven and bake for 12-15 minutes, or until the cheese is melted and bubbly and the crust is golden brown.
Remove from the oven and allow it to cool for a couple of minutes before slicing and serving.