When pot is hot, add onions, carrots, and celery. Season with salt and pepper, then saute until onion starts turning translucent on edges (about 5 minutes).
Stir garlic into veggies and cook, stirring constantly, until fragrant (about 30 seconds).
Add broth, then stir well to remove anything that might be stuck to the bottom of the pot. Turn off Instant Pot (press Cancel).
Mix mushrooms, tomatoes, potatoes, green beans, corn, basil, oregano, and bay leaf into soup.
Secure lid and set pressure release valve to Sealing. Select Pressure Cook button, then set to High Pressure for 1 minute.
When time is up, do a Quick Release, then open lid.
Stir in peas and zucchini. Cook until veggies are hot and tender, about 1 to 2 minutes.
Mix in parsley, then season soup generously with salt and pepper to taste.
Serve soup hot. Enjoy!
Notes
Make sure to use the Pressure Cook button on your Instant Pot for this recipe, NOT the Soup button.It's fine to substitute other veggies, however a 6-quart IP will be pretty much at max capacity with the recipe as written. So if you add extra vegetables, make sure to cut back on others.Because your Instant Pot will be so full, it's going to take a long time to come to pressure ... more than most IP recipes. It's hard to say exactly how long it will take, so I didn't include that in the cook time. Mine took about 30 minutes.If you are using bouillon to make your vegetable broth, you can throw the crumbled up cubes directly in the Instant Pot. No need to mix it with water first.The veggies in this recipe will be tender-crisp when the soup is finished cooking. If you'd prefer softer vegetables, cook the soup at High Pressure for 2 minutes, then do a Natural Pressure Release for 5 minutes.For extra flavor, stir in other fresh herbs (like basil) right before serving.