In a Dutch Oven melt the butter, add the olive oil and onions.
Cook on medium low heat for 30 minutes stirring occasionally, until a dark caramel color.
Add the garlic and wine and cook for a couple minutes.
Add the broth, Worcestershire, salt and pepper, thyme, bay leaf and beef base.
Simmer for 30 minutes
To serve toast the sliced bread.
Ladle soup into a ramekin and add a piece or two of the toasted bread.
Sprinkle with cheese and broil until cheese starts to turn brown.