1 lb boneless beef short ribs, trimmed and cut into 1/2 inch pieces
salt and pepper
2 TBS vegetable oil
8 oz. cremini mushrooms, trimmed and sliced 1/2 inch thick
1 onion, chopped fine
2 TBS tomato paste
2 tsp minced fresh thyme or 1/2 tsp dried
1 garlic clove, minced
2 TBS all-purpose flour
1/4 c dry red wine
6 c beef broth
1 lb red potatoes, unpeeled, cut into 3/4 inch pieces
3 carrots, peeled and cut into 1/2 inch pieces
2 celery ribs, cut into 1/2 inch pieces
2 bay leaves
2 TBS minced fresh parsley
1/ Pat beef dry with paper towels and season with salt and pepper. Heat 2 TBS oil in pressure-cooker pot over medium-high heat until just smoking. Brown half of meat on all sides, about 5 minutes; transfer to bowl. Repeat with 2 tsp oil and remaining beef.
2. Heat remaining 2 tsp oil in now-empty pot over medium heat until shimmering. Add mushrooms and onion and cook until softened, about 5 minutes. Stir in tomato paste, thyme, and garlic and cook until fragrant, about 30 seconds. Stir in flour and cook for 1 minute. Whisk in wine, scraping up any browned bits and smoothing out any lumps, and cook until slightly reduced, about 1 minute. Stir in broth, potatoes, carrots, celery, bay leaves, and beef with any accumulated juices.
3. Cook for 15 minutes: Lock lid in place and bring pot to high pressure over medium-high heat. As soon as indicator signals that pot has reached high pressure, reduce heat to medium-low and cook for 15 minutes, adjusting heat as needed to maintain high pressure.
4. Naturally release pressure: Remove pot from heat and let pressure release naturally for 15 minutes. Quick-release any remaining pressure, then carefully remove lid, allowing steam to escape away from you.
5. Discard bay leaves. Using large spoon, skim excess fat from surface of soup. Stir in parsley, season with salt and pepper to taste, and serve.
Omit potatoes. After discarding bay leaves in step 5, stir in 1/2 cup pearl barley and simmer until tender, about 15 minutes, then continue as directed.