if using it put the oil in the dutch oven, heat over medium heat until it shimmers and add the sausage and onion
If not using any oil then just saute sausage and onion as is
cook together together until sausage is browned and cooked through
Drain sausage if needed, leaving 1 tablespoon of grease
Add garlic, basil, Italian seasoning, ground mustard, and flour
Cook, stirring for about 30-60 seconds
Stir in chicken broth, tortellini, and salt
Bring to a simmer, and simmer for about 3 minutes
Stir in half and half and kale and continue to simmer an additional 3-5 minutes until kale is wilted and tortellini is done through
serve with optional parmesan cheese on top