Add all ingredients (except optional ingredients) to the Instant Pot or other electric pressure cooker. Stir. Secure the lid and set the vent knob to Pressure. Choose Manual or High Pressure and set the time to 2 minutes (use the minus button on the IP).
The Instant Pot will turn on and pressure will begin to build (this can take a while, from 15-30 minutes, depending on the temperature of your ingredients). When high pressure is reached, the counter will change to 2 and begin counting down. When it beeps, use the Cancel or Off button to turn off the cooker.
Very carefully, turn the vent knob to Steam (or use whatever quick steam release your cooker provides). To be extra careful, you can use a long-handled spoon to turn the knob so that you don't risk being burned by the steam. When the steam has all been released, the Instant Pot will unlock so that you can remove the lid, carefully angling it so that you don't get steamed.
Stir the soup. If you'd like it to be thinner, you can add water or vegetable broth. Check the flavor and add more seasoning as necessary. Add optional ingredients as desired.
I used the liquid from the canned beans because I find it results in a richer broth, but if you prefer to use water or vegetable broth, drain the beans, measure the liquid, and replace it with water or broth.The slowest part of Instant Pot cooking is waiting for the pot to reach high pressure. Thawing the vegetables beforehand or using fresh rather than frozen will shorten the cooking time.Finally, it's easy to make this soup on the stove, but you should start with 4 cups of water and add more as necessary because more water evaporates in stove-top cooking.This makes 6 average sized servings (about a cup and a half) or 4 meal-sized servings (about 2 1/2 cups each). A large serving is 1 point on Weight Watchers Freestyle.