In a large skillet over medium heat medium heat, cook the sausage until browned.
Cook the pasta according to package directions, and for a minute or two short of al dente.
In a large bowl, mix together the cooked sausage, cooked and drained pasta, spinach, red peppers, can of tomatoes (do not drain), oregano, and salt, and pepper. Season to taste with more salt and pepper if needed.
In a small bowl, mix the cheese together.
Prepare a 9x13 baking dish with cooking spray. Add the pasta mixture to the baking dish and top with the cheese mixture.
Bake for 25 minutes until the cheese is melted and golden and the edges are bubbly and starting to brown. Serve and enjoy!