For 6 Quart Instant Pot: Close the lid, set pressure vent to Sealing and press Pressure Cooking on High for 12 minutes.
After cooking is done, let 6 quart Instant Pot bring pressure down on its own - Natural Release. Do not do Quick Release, your beans will be undercooked or fall apart.
For 8 Quart Instant Pot: Close the lid, set pressure vent to Sealing and press Pressure Cooking on High for 12 minutes.
After cooking is done, let 8 quart Instant Pot bring pressure down on its own for 10 minutes and then release remaining pressure immediately. If you let your 8 Quart Instant Pot release pressure naturally all the way, black beans will be overcooked.
Open the lid. That’s it! Your Instant Pot black beans are ready.
Notes
Store: Cooked black beans refrigerate well for up to 5 days. You can use them in place of canned black beans with a ratio of 1.5 cups drained cooked beans = 15 oz can.
Freeze for later: Drain and rinse with cold water. Measure 1.5 cups (equal to a 15 oz can drained) into sandwich bags, let air out, seal and freeze for up to 6 months.
Thaw: Place bag with frozen black beans on a counter for a few hours or in the fridge overnight. You could also place it in a bowl with hot water for 5 minutes and then drain it.
Broth: Do not discard the liquid. Use as a base for making any soup. Especially, Instant Pot black bean soup
It is super important to use cold water not to alter cook time.
For 3 quart Instant Pot, I would cook beans for 15 minutes with natural release and go from there.