Barley, Beef and Kale Soup

1-tablespoon vegetable oil
1 onion, chopped
1 pound stew beef, diced
4 cups beef broth
1/2-cup barley
1 teaspoon dried thyme
1/2 teaspoon salt
1/2 pound mushroom, sliced
1 cup chopped kale

1. Heat oil in a kettle, or large, heavy saucepan over medium heat. Add chopped onion and diced stew beef; cook until well browned. Add beef broth, barley, thyme, and salt; bring to a boil. Reduce the heat, cover, and simmer about 1 hour, or until the barley and meat are almost tender. Add sliced mushrooms and chopped kale. Cover and cook 5 to 10 minutes more, or until the kale is cooked.