Turn the Instant Pot to its sauté function and warm the oil. Add onion and carrots, then cook for 3-5 minutes, until golden and slightly tender. Add garlic and cook 30-60 seconds more.
Pour in broth and scrape the bottom very well to remove any browned bits. Add crushed tomatoes, tomato paste, basil, oregano, thyme, salt, and pepper. Stir well. Close and seal the Instant Pot, and cook for 12 minutes on manual/high pressure.
When finished, allow an 8 minute natural pressure release, then vent remaining steam and open the lid.
Purée until smooth using an immersion blender, or by transferring the soup (very carefully!) in batches to a traditional blender.
Test and add extra salt and/or pepper to taste. Enjoy!
Notes
Yield: This recipe yields a fairly big batch of soup. It's easy to cut the recipe in half, but leftovers keep very well and can be frozen, so I find most people prefer the larger volume as a starting point. Worst case scenario: cook once, eat twice!
Cooking Time: The cooking time estimate of 30 minutes includes about 10 minutes for your Instant Pot to come up to pressure.
Storage: Keep soup refrigerated in an airtight container for 4-5 days.
Freezing: Store soup in an airtight freezer-safe container for up to 4 months. Thaw overnight in the refrigerator before reheating, if possible.
Reheating: Transfer soup to a Dutch oven or saucepan set on the stovetop over medium-low heat, and stir occasionally until wisps of steam and small bubbles rise from the soup. You can also reheat in the microwave; this tends to work best for small portions.