Pour the olive oil into a soup pot or Dutch oven and bring over medium-high heat. Add the onions and stir to coat. Cook, stirring occasionally, for a few minutes until the onions are softened. Add the minced garlic, stir together and cook for another 30-60 seconds. Add the sausage and stir together. Cook, breaking the meat up into small pieces, until the sausage is cooked through and fully broken up.

Add the broth, crushed tomatoes, basil, Italian seasoning, salt, pepper and red pepper flakes, increase the heat and bring to a boil. Once boiling, reduce the heat to low and simmer, covered, for 20 minutes. Uncover the pot and add the cream cheese. Whisk the cream cheese in while simmering until the cheese is dissolved. Add the tortellini and spinach and stir together. Cover the pot and simmer for 10 minutes until pasta is cooked.