Heat a large pot or Dutch oven over medium heat and add olive oil or a light coating of cooking spray. Add the chicken sausage, breaking it up with a spoon as it cooks. Once browned, stir in the onion and cook for 2–3 minutes, until fragrant and softened. Add in garlic and saute for an additional minute.

Add in diced tomatoes, tomato paste, 4 cups of chicken stock into the pot. Place the whole or half head of cauliflower in the soup.

Bring the mixture to a simmer, cover, and cook for about 20 minutes, or until the cauliflower is very tender.

Carefully remove the cauliflower and transfer it to a blender with some of the broth from the pot. It may help to transfer it to a cutting board or large bowl first, because it will be very hot and soft. Blend cauliflower with ¼ cup of additional broth until smooth and creamy.

Meanwhile, add the tortellini and spinach to the pot, cover and cook for 3-5 minutes or until pasta is tender, but al dente.

Gently stir in cauliflower cream, ¼ tsp of salt, and add any additional stock needed to achieve the thickness you would like. This is a soup I like on the thicker side, but it will continue to thicken as it cools.

Add parmesan cheese and fresh basil for garnish and enjoy!