Step 1

In a 6-qt. electric multicooker use sauté setting on high to heat 1 Tbsp. olive oil. Season roast with 1 tsp. salt. Add roast to multicooker; cook 8 to 10 minutes or until well browned on both sides, turning roast once. Remove roast from multicooker.

Step 2

Add 1/2 cup water to the multicooker and stir to scrape up browned bits on bottom of pot. Press cancel setting.

Step 3

Return roast to multicooker. Add 7 1/2 cups cold water, the beef bones, onion, carrots, celery, mushrooms, tomato paste, thyme (if using), and bay leaf. Lock lid and adjust steam valve to seal. Set cooker on high pressure to cook 1 hour. Let stand 45 to 55 minutes to release pressure naturally. Carefully open lid.

Step 4

Strain broth through a fine-mesh sieve into a large heatproof bowl. Reserve roast meat for another purpose; discard bay leaf and remaining solids.

Step 5

Stir soy sauce and 1/2 tsp. black pepper into broth. Taste and, if you like, add additional soy sauce and pepper. Refrigerate until completely chilled. Remove and discard any fat that has hardened on the surface of the broth. Store broth in airtight containers in the refrigerator up to 4 days or freeze up to 3 months. Makes 7 to 8 cups broth.