Rich cheesy goodness - I love it! The first time I saw onion soup I found tempting was on a program I saw long ago - French Food at Home with Laura Caulder. Although I have not tried it yet, your post is a good reminder that I need to. Do you have a recipe?
My "recipe" is a bit of a moving target. I am always messing with it, trying to make it better. A couple things I've learned - the better the stock, the better the end result. Be sure to let the onions caramelize. It's a bit like making a dark roux - the longer you cook them (stirring constantly at the end) the more flavor you'll end up with. And, whether you use wine, sherry, or some other liquor, use one you'd enjoy drinking, a cheap one will not help the final flavor of the soup.
3 red & 3 sweet onions - sliced very thin and separated into rings
about 3 - 4 TBS butter
2 TBS minced garlic
1 C red wine
48 oz chicken stock
32 oz beef stock
(sometimes I use veal stock in place of some of the chicken stock)
a few sprigs each of fresh parsley and fresh thyme tied with 2 bay leaves
2 TBS Worcestershire Sauce
1 TBS anchovy paste (optional)
2 TBS balsamic vinegar
salt & pepper to taste (at end to adjust seasonings)
Put butter and sliced onions into large, heavy soup pot, Dutch oven, or crock pot insert (if it can be used on the stove) over med-high heat
Cook onions down until they are almost syrupy and well caramelized (stir frequently while cooking down and almost constantly as they begin to caramelize) This will take between 30 and 60 minutes
Add garlic and cook, stirring, for about two more minutes
Deglaze with red wine (or sherry, brandy, cognac, etc.)
Transfer to crock pot and add chicken and beef stock, Worcestershire Sauce, and anchovy paste
Add herb bundle
Cover and cook on low for 6 -8 hours (or high for about 4 hours)
Remove herb bundle
Add balsamic vinegar and taste for seasoning - adjust as needed
Cut thick slices of French bread and toast them
Fill oven proof bowls about 2/3's and top with slice of toasted bread
Add slice of cheese (Gruyere, Swiss, or Havarti) and some shredded Mozzarella and Asiago
Place bowls on sheet pan (to catch any dripping cheese) and put under broiler just until cheese melts and is golden
