Select the SAUTE setting on Instant Pot. Heat oil, add onion, carrot and garlic. Saute till the onions are soft and translucent.
Switch off the SAUTE setting. Add the diced tomatoes, all the seasonings like dried oregano, basil, thyme, salt, black pepper and vegetable broth. Stir everything well.
Close the lid securely, and turn the vent to "SEALING". Select the PRESSURE COOK/MANUAL (High Pressure) setting and set the cooking time to 1 minute.
When the instant pot beeps, allow the pressure to release naturally for 5 minutes, then release any remaining pressure before removing the lid.
Select the SAUTE setting, and add in the fresh tortellini. Stir and cook for 3-5 minutes or until they float to the top.
Stir in the baby spinach after turning off the heat. The spinach will wilt with help of residual heat.
Finally, add the heavy cream, and give a quick mix. Adjust the seasoning at this stage.
Sprinkle some grated parmesan cheese (optional) if desired and serve warm.