Step 1

Preheat the oven to 425°F. Place the bones in a large roasting pan (like what you'd roast a turkey in). Rub both sides of the 6 pounds beef bones with 2 tablespoons olive oil and sprinkle with 1 teaspoon kosher salt. Roast in hot oven for 30 minutes. Your kitchen will smell amazing.

Step 2

After 30 minutes, flip the bones, add the 2 large onions, 2 celery stalks, 3 large carrots, and 1 tablespoon tomato paste and continue to roast for another 20 minutes. Remove from oven.

Step 3

Use your largest stockpot. Ensure it is oven save if you'll be doing any of the cooking in the oven.

Step 4

Transfer all of the roasted meat and vegetables from the roasting pan to a very large stockpot. Using a total of 5 quarts of water, add 1-2 quarts at a time to the empty roasting pan, scrape sides, swirl it around, and then pour it into the stockpot to make the broth. Repeat until you have added a total of about 5 quarts of water to the pot, but make sure you get every bit of flavor possible out of that roasting pan.

Step 5

Add the 1 head of garlic, freshly ground pepper, 1 tablespoon fresh thyme, and 2 bay leaves to the pot. Bring to a boil (uncovered), and then reduce heat so that broth is percolating at a gentle simmer. Cook at this temperature for a minimum of 6 hours up to a full day. You can also transfer pot to a preheated 200°F oven (this is what I do to let it cook overnight).

Step 6

Transfer all of the roasted meat and vegetables from the roasting pan to a very large oven safe stockpot. Using a total of 5 quarts of water, add 1-2 quarts at a time to the empty roasting pan, scrape sides, swirl it around, and then pour it into the stockpot to make the broth. Repeat until you have added a total of about 5 quarts of water to the pot, but make sure you get every bit of flavor possible out of that roasting pan.

Step 7

Add the head of garlic, pepper, thyme and bay leaves to the pot. Transfer pot to a preheated 200°F oven and cook, uncovered, for 6 hours up to over night.

Step 8

Due to the size of the Instant Pot, plan on cooking in two separate batches.

Step 9

Add half of the roasted meat and vegetables to the Instant Pot (refrigerate remaining until ready to use). Add half of the garlic, pepper, thyme and bay leaves. Fill to the top level with water. Seal lid and cook on high pressure 1-2 hours (1 hour works, longer is better if you have the time).

Step 10

Repeat with remaining ingredients to make second half.

Step 11

Strain stock and discard solids. Drink, use in a recipe, or refrigerate until the broth is chilled If using within the next few days, keep refrigerated. Otherwise, freeze if using at a later time.