Heat your oven to 425 degrees. Place your bones on a baking tray, drizzle with olive oil and sprinkle with salt. Roast for 50 mins, flipping over after 25 mins.
Add the bones, veggies, vinegar, salt, bay leaves and pepper corns to the instant pot. Pour water over top to the max liquid line inside the instant pot. TIP: pour hot water on the baking tray and scrape up all the brown bits that you can and add those to the instant pot as well. Brown bits = flavor!
Put the lid on and close it tight. Make sure the vent is in the sealing position. Select the "soup" function and add time to 240 mins. Let it do its thing!
When the time is up, let the pressure release slowly on its own if you have time. If you don't, let it release slowly for at least 30 mins and then cover it with a towel and press the quick release button with a long utensil. Don't get close to the steam, it will burn you! The towel will help to reduce splatter.
Remove the bones and the big chunks of veggies. Pour the broth through a strainer and into a bowl or a fat separator to get rid of the fat. Or you can let it cool in the fridge and the fat will harden making it easy to scoop off.
Store in mason jars or other containers in the fridge or freezer.