from a crock pot cookbook
1/4 cup butter (that's right... only half a stick :)
3 large yellow onions, sliced thinly
1 cup dry white wine
(3) 14.5 cans beef broth
1 teaspoon Wocestershire sauce
1/2 teaspoon salt
1/2 teaspoon dried thyme leaves
4 slices French bread, toasted
4 slices mozzarella cheese
Melt butter in large skillet over medium heat. Add onions, cook for 15 minutes or until onions are soft and lightly browned. Stir in wine. Combine onion mizture, broth, Worcestershire sauce, salt and thyme in slow cooker. Cover; cook on LOW 4 to 4 1/2 hours. Preheat broiler. Ladle soup into 4 oven-safe bowls; top with bread and cheese. Place beneath broiler until cheese melts and just starts to brown.
I'm a little hesitant to cook with wine. So I substitued it for chicken stock... then I regretted it. The soup was good, but it was obviously missing something since I skipped out on the wine. So don't skip the wine!