Chop all the vegetables and have it ready.
Place the inner pot of the instant pot and turn it on saute mode.
When the pot displays 'Hot', add the olive oil.
Add the chopped onions and celery and mix well. Let them saute until lightly translucent (about 3 minutes).
Then add the garlic and saute for few seconds.
Now add the Chopped carrots and zucchini and saute them for couple of minutes.
Next add the diced tomato and tomato sauce and mix well.
Pour the vegetable broth and mix well. Add the salt, pepper and the Italian seasoning and give it a good mix
Also add the pasta to the pot and mix. This makes the pasta a little mushy and hence I prefer to cook the pasta separately and then add it to the soup at then end when adding the spinach.
Give it a good stir and turn off the pot. Place the lid of the Instant pot and place the vent on 'sealing' position.
Turn on the Instant pot on 'Manual' and set it for 4 minutes on high pressure.
Once the Instant pot turns off after finishing the cycle, do a quick release in 10 minutes.
Open the pot and add the washed spinach leaves to the soup. Also add the cooked pasta. Mix it well and cover the pot again so that the spinach leaves wilts a little in the heat.
After about 5 minutes, open the pot and check for seasoning. Add more salt and pepper, if needed and serve hot sprinkled with freshly grated Parmesan cheese.