⅔ pound sweet Italian sausage, removed from its casing
2 tablespoons olive oil, divided
½ teaspoon fennel seeds
1 medium yellow onion, thinly sliced
1 red bell pepper, cut into thin matchsticks
1 orange bell pepper, cut into thin matchsticks
1 yellow bell pepper, cut into thin matchsticks
1 teaspoon chopped fresh rosemary
sea salt and freshly ground black pepper, to taste
1 teaspoon sugar
1 tablespoon red wine vinegar
1 15 oz. can tomato sauce
1 cup heavy cream
2 cups shredded cheddar and Gruyère mélange cheese (see notes)
½ cup shredded Asiago cheese
Instructions
Bring a large pot of salted water to a boil. Cook pasta until al dente according to package directions. Drain and transfer to a large bowl.
In the same pot used to cook the pasta, brown sausage over medium heat, breaking it into bite-size pieces with a spoon. Once sausage is browned, transfer to bowl with pasta and toss to combine.
Add 1 tablespoon olive oil to pot and heat over medium-high heat. Add fennel seeds and cook, stirring often, until fragrant, about 1 minute. Add onion, cover and cook, stirring occasionally, until slightly caramelized, about 10 minutes. Transfer to bowl with pasta and sausage.
Preheat oven to 425 degrees.
Add remaining 1 tablespoon olive oil to pot and heat over medium-high heat. Add bell peppers and rosemary, season with salt and pepper, and cook, stirring occasionally, until tender, 3-4 minutes.
Add sugar and red wine vinegar and cook for 1 minute. Add tomato sauce and heavy cream. Bring to a boil, reduce heat and simmer until slightly thickened, about 5 minutes.
Add pasta mixture and cheddar and Gruyère mélange cheese to pot and stir to combine. Season with additional salt and pepper to taste. Transfer mixture to a greased 9"x13" baking dish, or a greased 9" square baking dish and a small oven-safe bowl.
Top with Asiago cheese and bake for 10-15 minutes or until cheese is melted.
Notes
I used this cheese from Trader Joe's, but you can substitute a mix of white cheddar and Gruyère cheese if it's more convenient.
Recipe by Two of a Kind at http://www.twoofakindcooks.com/baked-rigatoni-with-sausage-bell-peppers/