In a large pot over medium-high heat, add Italian sausage, breaking it into pieces. Cook for 7-10 minutes until browned. Remove and set aside, leaving fat in the pot.

Lower the heat to medium and add diced onion and chopped celery. Sauté for 4-5 minutes until soft.

Sprinkle flour over the vegetables, stirring continuously for 1 minute to form a roux. Add minced garlic and cook for 30 seconds.

Gradually pour in chicken broth while stirring. Return sausage to the pot and bring to a gentle boil.

Stir in diced tomatoes and Italian seasoning, adjusting salt and pepper to taste. Simmer for 2-3 minutes.

Add cheese tortellini, cooking for about 5 minutes until al dente.

Pour in heavy cream and stir well, simmering for another 5 minutes.

Fold in fresh spinach until wilted, about 1-2 minutes. Adjust seasoning if needed before serving.