I am, admittedly, a French onion soup fanatic. I order it whenever I spot it on a menu, whether it’s an upscale French brasserie or a strip-mall Red Robin, and I’m constantly trying to perfect my own version. I’ve tried recipes with bacon (overwhelms everything), recipes with Vidalias or Walla Walla sweets (too cloying), recipes using a mixture of chicken broth and beef broth (too thin-tasting), red onions versus yellow onions, $25-a-pound Gruyère versus store-brand Swiss cheese, you name it. The perfect French onion soup, in my mind, should be beefy and full-bodied, cheesy but not all about the cheese, and redolent with caramelized-onion flavor without being too sweet. And, at long last, I believe I’ve been able to strike that balance, using an ingredient I actually had set aside for another dish.
I was pretty proud of myself for discovering this, only to have a Google search lead me to the evidently quite popular “Guinness and onion soup.” But most versions seem to consist of a quick sauté of onions and some beef broth, rather than making a real French onion soup from scratch. So, original or not, this is the best version I’ve made yet—beefy, slightly sweet, and slightly bitter. As below it makes about 6 servings.
• 8 cups sliced (pole-to-pole, so they’re not stringy) onions (it’s cheapest to buy one of those pre-packaged 3-pound bags from the supermarket): $1
• 1 T fresh thyme leaves (garden): $0
• 3 T butter, cut into cubes: 18 cents
• 3 T balsamic vinegar (this is cheapest at Costco, I’ve found): 25 cents
• 1 cup Guinness: $1
• 6 cups beef stock or broth (I used Better Than Bouillon base): 30 cents
• 6 slices country bread: 11 cents
• 6 slices Gruyère or Irish cheddar, grated (I used Kroger brand extra-sharp white cheddar): $2.20
• Salt: 1 cent
TOTAL: $5.05/6 = 84 cents/serving
Preheat the oven to 400 degrees. Combine the sliced onions with the butter and 1 tsp table or fine sea salt in an oven-proof pot with lid, preferably a dutch oven. Stir well, cover, put in the oven, and bake for 2 1/2 hours, stirring the onions every 30 minutes so they don’t burn. (I learned this technique from Cook’s Illustrated a while back; it may seem like a long time, but it sure beats having to pay attention to them on the stove for an hour or more.)
When finished, put the pot with the onions on a burner on medium heat. Add the thyme leaves.
When the onions start to stick to the bottom, deglaze with the balsamic vinegar. When they start to stick again, add the beer. Cook until beer has reduced by about half, then add the beef broth. Bring to a boil, reduce to a simmer, and cook, partially covered, for 30-40 minutes, until flavors have melded. Adjust seasoning to taste.
Meanwhile, toast the bread slices. (If they’re too thick to fit in the toaster, do this in the oven.) If you, like me, do not have broiler-safe bowls, sprinkle the cheese over the bread slices and broil until cheese is bubbly and browned. When the soup has been ladled into bowls, place a cheese-covered bread toast in each.
If you do have broiler-safe bowls, when soup is done, ladle it in the bowls, add the toast, sprinkle it with cheese, and broil until cheese is bubbling and browned.
For leftovers, put the soup in a separate container; keep extra bread toasts on a plate in the fridge.