Bring a large pot of salted water to a rolling boil. Add your pasta and cook until al dente according to package directions. Reserve one cup of pasta water before draining.

Meanwhile, heat olive oil in a large skillet over medium-high heat. Remove sausage from casings if using links. Break the meat into bite-sized pieces as it cooks. Brown the sausage thoroughly, about 6-8 minutes.

Once the sausage browns completely, add minced garlic. Cook for about 30 seconds, stirring constantly.

Pour in chicken broth to deglaze the pan. Scrape up all those beautiful browned bits from the bottom. Let the broth reduce slightly, about 2 minutes.

Reduce heat to medium-low. Add heavy cream and stir well. Let the mixture simmer gently for 3-4 minutes.

Remove the skillet from heat. Add freshly grated parmesan gradually, stirring constantly.

Add the drained pasta directly to the skillet. Toss everything together thoroughly. If the sauce seems too thick, add reserved pasta water one tablespoon at a time.

Stir in fresh basil and red pepper flakes. Season with salt and black pepper to taste. If using spinach, add it now.