Vegetable Beef and Barley Soup

Name: Vegetable Beef and Barley Soup
Ingredients: 3 medium carrots (peeled and sliced into coins); 3 medium leeks (washed and sliced); 1 large yellow onion (diced); 3 medium turnips (peeled and diced); 1 pound mushrooms (cleaned and halved); 1½ tablespoons avocado oil (or other neutral oil safe for high heat); 2 pounds beef short ribs (bone-in or boneless (see notes)); kosher salt; 8 cups beef stock (fat free); 1/2 cup pearled barley (not quick cooking barley); 3/4 cup frozen peas; freshly ground black pepper (more or less to taste)