Quickly sort through the black beans, making sure there are no small rocks in them. Add beans to Instant Pot.
Add water, onion, garlic, salt, cumin, chili powder and oregano to Instant Pot. Stir so everything is combined. Cook on HIGH PRESSURE for 30 minutes. Let the beans rest, naturally releasing the pressure, this takes about 20 minutes. Once steam has escaped, carefully remove the lid.
Drain beans as there will be excess liquid. Enjoy the black beans immediately, store in refrigerator for up to 3 days, or freeze in freezer bags for up to 6 months.
Notes
If you'd like a smaller batch of beans simply cut all the ingredient amounts in half.