Step 1

Pour the tomatoes and their liquid into the Instant Pot. Place the other ingredients on top of the tomatoes, keeping them off the bottom of the pot as much as possible (especially the tomato paste). Press the garlic and herbs down into the liquid a little to moisten, but they should still be visible. Don't stir! (You want to avoid a 'burn' error. See notes.)

Step 2

Secure the lid on the Instant Pot and make sure the vent is set to sealed/closed. Set to Manual Pressure (high), 25 minutes. When the pot beeps (after 25 minuteuse the Natural Pressure Release method, allowing the pressure to release for 10 minutes. Then, carefully open the vent, and remove the lid.

Step 3

Remove the onion pieces and discard. Blend or mash the sauce using an immersion or regular blender, or food processor, or by hand with a potato masher and/or large fork. Blend to your desired consistency--either chunky or smooth.

Step 4

Prepare the ingredients according to the directions above. Place them in a large pot, stir them together, and simmer, covered, on medium low heat for at least 30 minutes. Howver, I recommend 45-60 for a fuller-flavored sauce.