Place the oil in the Instant Pot and select “Sauté”. Then add the mushrooms, onion and garlic and cook for about 5 minutes.
Add the zucchinis, basil, salt and black pepper and cook for about 1-2 minutes.
Select the “Cancel” and place tomatoes with juice on top of vegetable mixture.
Secure the lid and cook under “Manual” and “Low Pressure” for about 1 minutes.
Select the “Cancel” and carefully do a Natural release.
Remove the lid and serve hot.