Savory French Onion Soup

I don't know how anyone could not like french onion soup.  It is so rich, so bubbly with melted cheese, so satisfying!  I actually burned my tongue pretty badly when I made this - I just couldn't resist taking a bite right after it came out of the oven.  My tongue hurt for like 4 days, but I guess it was worth it.

Ingredients:
4 medium white or yellow onions, thinly sliced
4 garlic cloves, minced
4 tablespoons of butter
2 tablespoons balsamic vinegar
2 tablespoons brown sugar
3 tablespoons flour
8 ounces of beer
64 ounces beef stock (to make vegetarian, substitute vegetable stock and double the flour)
3 tablespoons fresh thyme

1 teaspoon fresh oregano

2 tsp beef bouillon (optional - see below)
Salt and pepper, to taste

1 loaf French bread

Gruyere or provolone cheese, sliced

Directions:
Melt butter in a large pot, then add onions, garlic, brown sugar,  and balsamic vinegar.  Sprinkle with salt and pepper.

Cover and let cook for about 30 minutes, stirring occasionally, until onions are caramelized.
Add flour and stir, then let sit for 5 minutes.  Add beer, beef stock, oregano and thyme, and then turn heat to low.  Note - I used homemade beef stock, which has no added salt.  At the end of the cooking time, the soup didn't seem quite tasty or salty enough, so I added about 2 teaspoons of beef bouillon.

Cover the soup and cook for 1-2 hours.  While soup is cooking, slice french bread into round slices.  When soup is ready, taste and add additional seasoning, if necessary.

Fill oven safe soup bowls with the soup.  Top each bowl with a slice of French bread, and a slice (or two, if you want it extra cheesy!) of cheese.  Place bowls under the broiler for 2-3 minutes, or until cheese is bubbly and golden brown.  Remove with a pot holder, as bowls will be extremely hot.  For the safety of your tongue, do not sample for at least 5 minutes!

Note - I've made this soup many times, but this was the first time I used a recipe that called for beer.  I thought it really added to the depth of flavor.  I would suggest a dark beer (I used Negra Modelo).  Enjoy!