Beef and Cremini French Onion Soup

Heat olive oil in a 4-quart Dutch oven over medium-high heat.  

Add beef cubes and cook about 5 minutes, stirring occasionally until beef is brown.

Remove beef from Dutch oven, reserving drippings, and set beef aside.

Add butter to reserved drippings and heat over medium-low heat.  Add onions and cook, covered, for 5 minutes.  Add mushrooms and cook, covered, another 5 minutes or until onions are golden, stirring occasionally.

Stir in beef, broth, wine, Worcestershire sauce, bay leaf, thyme and pepper.  Bring to a boil, reduce heat and simmer, covered, for 30 minutes.  Discard bay leaf.

Meanwhile, place toasted baguette slices on baking sheet.  Evenly divide cheese among slices.  Broil 3 to 4 inches from heat for 3 to 4 minutes or until cheese is light brown and bubbly.  

Ladle soup into bowls.  Top each serving with bread slice.