Add browned sausage, veggies, seasonings and broth to slow cooker.
Cook on low 7-8 hrs or high 4 hrs.
Skim any fat from top. Whisk in cornstarch slurry and milk/half-and-half.
Add tortellini, cover and cook on high 45 mins until thickened.
Stir in spinach until wilted, about 5-10 mins.
Add 1 cup milk, plus more as needed for desired creamy consistency.
Season with salt and pepper to taste.
Serve warm with crusty bread.