Set Instant Pot to saute on normal (medium) Add butter, onion and garlic. Saute about 5 minutes until softened.
Add in sausage meat and cook until no longer pink, and crumbled.
Pour in chicken stock, then diced tomatoes, do not stir. Place baby spinach on top.
Cancel saute, and set instant pot to pressure cook on high for 6 minutes. Once time is up, do a quick release. Watch the steam, it's HOT!
Cancel pressure setting and set to saute on medium. Stir in tortellini and cover for 3-4 minutes. Open lid, stir in half and half, heavy cream and Parmesan cheese. Adjust seasoning to taste and serve.