Remove the sausage from the casings and set aside.
Set the Instant Pot on SAUTE and keep it on NORMAL. Add olive oil and when the oil becomes hot gently release the ground sausage and brown them nicely.
Once, the sausage is nicely browned add the chopped onion and garlic and saute for 1 minute.
Next, pour the chicken stock, the water, add the diced tomatoes, tomato paste and all the seasonings. De-glaze the pot very well with the help of a spatula so that there are absolutely no bits and crumbs stuck at the bottom of the pot.
Throw in the tortellinis and give everything a good stir. CANCEL the SAUTE.
Close the lid of the Instant Pot. Seal the valve and press the PRESSURE COOK button and set it on HIGH for just 2 minutes.
When the cooking cycle is over the Instant Pot will begin to beep. Immediately perform a quick pressure release by moving the valve from the SEALING to the VENTING position.
Open the pot. Turn off the Instant Pot.
Add the heavy cream and the parmesan cheese and gently stir to fully incorporate them into the soup.
Once the cream and the cheese is fully incorporated add the baby spinach and mix well.
Wait for 1-2 minutes and than serve the creamy Tortellini Sausage Soup hot. The residual heat will wilt the spinach and the soup will taste amazing. Enjoy!