-Preheat oven to 350 degrees Fahrenheit (175 Celsius).
-Spray a 9x13 baking sheet lightly with cooking spray.
-Unroll your crescent dough and press firmly into your baking sheet, taking care to press all the seams together (if needed) to form one uniform sheet of dough.
-Dock the dough with a fork so as crust prebakes it will stay uniformly flat and not bubble up.
-Prebake the dough for approximately 15 minutes, or until lightly golden.
-Remove from the oven and allow it to cool while making the scrambled eggs.
-In a large bowl, whisk the eggs, sour cream (optional), milk, salt, pepper, and Dijon mustard until light and fluffy.
-In a large skillet over medium-low heat, melt the butter and gently scramble the egg mixture until you reach a slightly wet consistency. *Note - You'll still be baking the pizza off in the oven, so you don't need to thoroughly cook the eggs at this point.
-Remove the skillet from the heat and set it aside.
-Place the American cheese slices evenly over the top of the parbaked crescent roll crust.
-Gently spoon the scrambled eggs evenly over the entire surface of the pizza crust and cheese slices.
-Top with the scrambled eggs with cooked sausage and shredded cheddar cheese.
-Bake the entire pizza for an additional 5 minutes until the cheese has melted and the crust is fully cooked. Top with chopped scallions if desired.
-Allow to cool for a few minutes, slice, and serve.