In a large skillet, heat olive oil over medium-high heat. Add red pepper and onion and sauté until softened, about 8 minutes. 

Stir in the garlic, fennel, red pepper flakes, and a large pinch each of salt and pepper. Crumble sausage into the skillet and cook with the pepper and onion until browned.

Deglaze the skillet by adding the wine and scraping the cooked bits off the bottom.

Add the marinara sauce, pasta, and 3 cups of the water and mix well. Bring to a boil, then reduce heat to medium-low and cover. Simmer 15 to 17 minutes or until pasta is cooked through, adding the remaining cup of water in small amounts every 5 minutes or so, and stirring to prevent the pasta from sticking to the bottom of the skillet.

Stir in cream, Parmesan cheese, and most of the basil (reserve some to use as a garnish when serving). Allow cream to heat through for about 2 minutes. Remove from heat and cool for 5 minutes before serving.