Optional step: roast the bones on a sheet pan at 425 degrees for 30 minutes, turning halfway through. This will give the broth a rich flavor and a darker color.
Add the bones, carrot, celery, onion, salt, pepper, and apple cider vinegar to your kitchen droid's inner pot (Instant Pot).
Pour water over the ingredients until you reach the 2/3 Max line your 3qt droid (5-6 cups)
Lock the lid and make sure the steam release valve is set to the sealing position
Select Pressure Cook (high) and set the cook time for 4 hours.
When the cook time is finished, allow the pressure to release naturally for at least 30 minutes before quick releasing any remaining pressure.
Strain out the bones and vegetables using a fine mesh strainer and discard. Store cooled broth in the refrigerator for up to a week. Freeze to store even longer.
Enjoy sipping this broth warm (add more salt to taste) or use in any recipe that call for beef (or gringer) broth or stock.
If you are using a 6qt kitchen droid (Instant Pot) this recipe can be doubled. If you are using an 8qt, it can be tripled. Just make sure you don't fill your inner pot with water above the 2/3 Max line in your pot.