Preheat the oven to 450°F. Place the sausage links onto a sheet pan and drizzle with olive oil. Rub to coat. Roast for about 12 minutes, or until just cooked through. Transfer the sausage to a cutting board. Once cool enough to handle, slice the sausage into ¼” pieces.

Meanwhile, bring a large pot of generously salted water to a boil. Once boiling, drop the rigatoni. Stir well and cook for 2 minutes less than the package’s instructions.

Simultaneously, heat a large, heavy-bottomed pot over medium-high heat. Add the ¼ cup of olive oil. Once hot, add the sliced sausage. Cook for 2-3 minutes, or until browned. Add the cherry tomatoes and a pinch of salt. Cook for another 3 minutes or so until the tomatoes burst open and release some juice. Stir in the garlic, oregano, and red pepper flakes.

Pour in the marinara sauce and stir in the spinach. Retrieve a ½ cup of starchy pasta water from the pot and add it to the sauce. Bring the sauce to a simmer as the spinach wilts. Stir in the parmesan cheese and let it melt.

Drain the pasta when it’s done and add it right to the sauce, along with the parsley. Stir to combine.

Grease a 12” cast iron skillet (or 9x13x3” baking dish) with olive oil. Pour in half of the pasta. Top with half of the shredded mozzarella. Pour in the remaining pasta. Top with the sliced fresh mozzarella and remaining shredded mozzarella. 

Bake for 8 minutes, or until the cheese is melted. Broil on high for 1-2 more minutes until golden. Serve with a pinch of parsley and grated parmesan over top.