Begin by heating olive oil in a large pot over medium heat. Sauté the chopped shallot until softened and fragrant. Add the chicken sausage, breaking it up with your spoon, and cook for 5–8 minutes until browned. Stir in the minced garlic, letting it cook for about 30 seconds to release its aroma.

Pour the crushed San Marzano tomatoes into the pot and follow with the vodka or chicken broth. Stir in the pesto, oregano, rosemary, and a pinch of salt and pepper for seasoning. Lower the heat and simmer, allowing the sauce to reduce slightly and flavors to meld beautifully.

Add 2½ cups of water directly to the sauce, then stir in the uncooked rigatoni and shredded kale. Increase the heat to bring it all to a boil, stirring occasionally to keep the pasta from sticking. Cook until the rigatoni is just al dente, as it will finish cooking in the oven.

Once the pasta is tender, mix in half of the shredded fontina cheese until melted and creamy. If your pot is oven-safe, spread the remaining fontina, torn mozzarella, and extra dollops of pesto on top. Otherwise, transfer everything to a greased baking dish before adding the cheeses.

Preheat your oven to 350°F. Bake your dish uncovered for 20–25 minutes, or until the cheese is bubbly and golden with a crunchy, crispy top. Garnish with a sprinkle of fresh rosemary or basil and serve it hot!