Step 1

Preheat oven to 350°F.

Step 2

Bring a large pot of salted water to a boil. Cook pasta shells 1 minute before al dente, strain, and rinse with cool water to prevent overcooking.

Step 3

Meanwhile, in a cast-iron skillet, cook sausage until fully cooked through and browned. About 5-7 minutes. Use the tip of a spatula to break the sausage into the smallest chunks possible as it cooks. Season with salt and pepper to taste and remove the pan from the heat.

Step 4

Transfer the sausage to a medium bowl with ricotta, basil, garlic, parmesan cheese, and egg. Stir until fully incorporated and creamy. Place 1 cup of marinara in the bottom of the now-empty skillet.

Step 5

Cut a 1-inch hole in a pastry bag or corner of a large Ziploc bag. Transfer the ricotta filling to the bag and fill each shell to the top with ricotta. You can alternatively fill shells with a spoon.

Step 6

Arrange shells in the skillet as tightly as possible. You can usually fit 20-22 shells in a 12-inch cast iron skillet. Top each shell with a heaping tablespoon of marinara. Layer the entire dish with about 1 cup of shredded mozzarella (more is OK too).

Step 7

Bake for 20-25 minutes or until cheese is fully melted and golden. Finish with a quick broil to give the cheese a little sear if desired. Let cool for 5 minutes, top with extra chopped basil, and serve immediately.