Prep the Baking Dish: Spray two 9x13-inch baking dishes with non-stick cooking spray and set aside.

Cook the Sausage: In a large skillet over medium heat, cook 1 pound of ground breakfast sausage until no pink remains, about 5-7 minutes. Stir in the undrained diced tomatoes and green chiles. Combine and transfer to a mixing bowl.

Brown the Hashbrowns: In the same skillet, melt 2 tablespoons of butter over medium heat. Add 20 ounces of frozen shredded hashbrowns, seasoning with ¼ teaspoon salt and ¼ teaspoon pepper. Cook for 8-10 minutes until browned. Combine with sausage mixture and stir in 2 cups of shredded cheese.

Assemble the Burritos: Take a flour tortilla and place roughly ¼ cup of the sausage and hashbrown mixture in the center. Roll tightly and place seam-side down in a prepared baking dish. Repeat until all filling is used.

Prepare the Egg Mixture: In a large bowl, whisk together 12 eggs, 1 cup half and half, 1 cup sour cream, and the remaining ¼ teaspoon salt and pepper until fluffy. Pour evenly over the tortillas and top with ½ cup of shredded cheese.

Chill the Casserole: Cover the baking dishes tightly with plastic wrap and refrigerate for at least 30 minutes, or overnight.

Bake the Casserole: Preheat the oven to 350°F. Let the dish sit at room temperature for 10 minutes before baking uncovered for 30-40 minutes until set.