Thoroughly rinse the beans under cold running water. Drain thoroughly and set aside.
Set your Instant Pot to sauté function, medium heat. Add the olive oil and onions and sauté for 3-4 minutes, stirring often. Add the red and green bell pepper and continue to cook for an additional 3-4 minutes, stirring often (if you notice the onions start to brown too quickly, reduce the heat to low and add a few tablespoons of water to help deglaze any brown bits that may be sticking to the bottom of the pot). Add the garlic and mix well to combine.
Turn off sauté mode. Check to make sure nothing is stuck to the bottom of your pot. If there is, add a little water and scrape it off with a metal spatula.
Add the remaining ingredients (minus any optional toppings). Mix thoroughly to combine.
Secure the lid on top of the Instant Pot, making sure the valve is in the "sealing" position. Set the Instant Pot to "manual" mode and set the timer for 35 minutes. Press start.
Remember: it takes about 15 minutes for your Instant Pot to reach full pressure before the time will start to count down.
Once the countdown has finished, allow the pressure to release naturally for 15, then do a quick release to release any additional pressure. Carefully remove the lid and stir.
Use an immersion blender to puree the soup directly inside your Instant Pot. Or, transfer to a large blender and blend it there. Season with additional salt and pepper, to taste. Serve garnished with all your favorites - avocado, cheese, red chili flakes, sliced red onion, sour cream, etc.