Heat the olive oil in a medium to large saucepan or stockpot. Add the garlic and cook until fragrant, about 2 minutes.
Add the ground Italian sausage and cook until browned, breaking the pieces up into bite sized chunks (like you would make for ground beef tacos).
Stir in the tomato paste, crushed tomatoes, and all of the spices. Simmer for about 20 minutes, stirring occasionally.
While the marinara is simmering, preheat the oven to 350°F.
Then, cook the rotini pasta according to package directions and drain.
Mix the cooked pasta with the marinara sauce along with about 4 ounces of the pepperoni, stirring to combine.
Place the pasta mixture into a lightly greased 9x13 baking dish.
Top with the mozzarella cheese and remaining pepperoni.
Bake for about 20-25 minutes, or until the cheese is fully melted and has started to brown.
Serve immediately and enjoy!