Adjust rack to middle position and preheat oven to 400 degrees. Bring a large pot of salted water to a boil. Wash and dry all produce. Halve bell pepper; discard stem and seeds. Thinly slice chili. Remove sausage from casing; discard casing.

Drizzle bell pepper halves with oil and season with salt and pepper; place cut sides down on a lightly oiled baking sheet. Place garlic cloves in the center of a small piece of foil. Drizzle with oil and season with salt and pepper; cinch into a packet and place on same sheet. Roast until bell pepper is lightly charred and garlic is softened, 20-25 minutes.

Once water is boiling, add cavatappi to pot. Cook until al dente, 9-11 minutes. Reserve 1 cup pasta cooking water (2 cups for 4 servings), then drain.

Heat a drizzle of olive oil in a large pan over medium-high heat. Add sausage and cook, breaking up meat into pieces, until browned and cooked through, 4-6 minutes. (TIP: If there’s excess grease in your pan, carefully pour it out.) If desired, stir in a pinch of chili; cook until fragrant, 15 seconds. Add tomato paste and 1/2 cup reserved pasta cooking water (3/4 cup for 4 servings). Simmer until thickened, 2-3 minutes. Turn off heat.

Transfer roasted bell pepper and garlic cloves to a cutting board. Thinly slice bell pepper into strips; mash garlic with a fork. Return pan with sauce to low heat; stir in garlic. Cut top off carton of cream sauce to open fully; pour contents into pan. Using a spoon or spatula, scrape any remaining sauce from carton into pan. Stir in bell pepper, cavatappi, half the Parmesan (you’ll use the rest later), and 2 TBSP butter (4 TBSP for 4 servings). TIP: If needed, add more reserved cooking water a splash at a time until pasta is coated in a creamy sauce.

Season pasta with salt and pepper and divide between bowls. Sprinkle with remaining Parmesan and, if desired, a pinch of remaining chili.