In a large colander, rinse the black beans under cool water. Remove any broken beans or small stones.
Add the black beans, 6 cups of water, onion, garlic, chili powder, cumin, salt, and oregano to the Instant Pot insert.
Place the lid on the Instant Pot and twist and seal to lock. Turn the steam release valve to “sealing”. Set the Instant Pot to high pressure for 25 minutes. Let steam release naturally, for 25 minutes, then release manually.
Remove the lid from the Instant Pot. Add the lime juice and season with more salt to taste.
Notes
For thicker black beans, you can drain off the liquid after cooking or mash ½ to 1 cup of the beans and stir them back into the pot.
To soften the flavors of the onion and garlic, use the saute function to cook them until starting to brown in 1 to 2 tablespoons of olive oil before pressure cooking the black beans.
Use a 6-quart Instant Pot. This is the ideal size for this recipe. If using a smaller Instant Pot, remember that the contents should not pass the max fill line. You may need to scale the recipe down to fit into a smaller pot.