2. Heat a large nonstick skillet over medium-high heat. Add steak; saute 5 minutes or until browned. Place steak in a 3-quart electric slow cooker. Add sliced onion and garlic to pan; coat with cooking spray, and saute over medium-high heat 5 minutes or until tender. Lightly spoon flour into a dry measuring cup; level with a knife. Sprinkle flour over onion-garlic mixture; cook 1 minute, stirring constantly. Gradually add broth, wine, and tomato paste, stirring constantly. Cook 1 minute or until thick. Add pearl onions, dried thyme, salt, pepper, bay leaf, and mushrooms.