Instructions

1. Bring a large pot of salted water to a boil. Add the rigatoni and cook according to package directions. Drain, reserving 2 cups of starchy pasta water.
2. Heat olive oil in a large deep pot over medium high heat. Add the celery and onion and cook until very soft, about 10-15 minutes. Add the sausage and cook, breaking into small pieces until browned and crispy.
3. Reduce heat to medium-low and add in the garlic, fennel seeds and tomato paste. Saute until paste is lightly browned, about 2 minutes. Add in the wine or broth and cook, scraping the bottom of the pot to get the browned pieces of sausage that have stuck to the pain. Cook until reduced, about 4-5 minutes.
4. Add in the cashew cream, spinach and 1/2 cup reserved pasta water. Let simmer for 5 minutes and add in the salt to taste.
5. Add in the cooked pasta to the sauce and add a little reserved pasta water at a time, stirring to incorporate, adding as much pasta water as needed to let the sauce cling to the noodles. Stir in red pepper flakes, if desired, and serve.