Place the chicken wings in the bottom of the Instant Pot. Top with the onions, celery, carrots, parsley, peppercorns, garlic, and bay leaves. Fill 2/3 of the way full with cold water.
Close the lid, making sure the top valve is set to "Sealing." Turn the Instant Pot on and press the manual button (keep the default setting of high pressure). Set the time for 60 minutes.
Once the stock is finished, I recommend letting the steam release naturally, since it can be very hot and a small amount of hot liquid might spit out the top. If you release the pressure manually, turn and hold the valve using kitchen tongs to keep your hands safe.
Ladle the stock through a fine mesh strainer into a large bowl, then discard the solids. If possible, you should line the strainer with cheesecloth to catch any tiny particles.
Cover the stock and place in the refrigerator to chill until the fat to rises to the surface. If you're in a hurry, you can speed up the process by using several smaller bowls or storage containers. You can also use the freezer (but watch carefully to make sure the stock doesn't actually freeze).
Once the stock is cold and jiggly, use a ladle to skim and discard the fat from the top. Don't dispose of the fat in your sink; it will clog the drain.
Store in an airtight container in the refrigerator for 3-4 days or in the freezer for 3 months (or longer).
You can use any pressure cooker to prepare this recipe, but you’ll need to adjust the cooking instructions based on manufacturer settings. Before freezing, I recommend placing the stock in various sized deli cups. That way you can defrost only what you need.