Recipe

Make Croutons

1. Preheat oven to 375°F, with rack in center position. In small bowl, mix butter with garlic. Place bread chunks on baking sheet, drizzle with melted butter mixture, and season with salt and pepper, then toss until well combined. Bake, tossing occasionally, until golden brown, 15 to 20 minutes. Let croutons cool completely. Store leftover croutons in airtight container for up to 3 days. When ready to use, warm them up in a 350°F oven for 5 minutes.

Make Onion Stock

1. Slice 4 onions 1⁄2″ thick. In large pot on high heat, heat 1⁄4 cup of oil, until smoking hot. Add sliced onions and cook, stirring, for 5 minutes. Lower heat to medium-low and add thyme, garlic and bay leaf. Continue slowly cooking onions, stirring occasionally, until dark golden and nicely caramelized. Done properly, caramelization process will take 60 minutes or more.
2. Once caramelized onions are ready, pour in stock and bring to a simmer on medium-high heat, then lower heat to low and cook gently for 15 to 20 minutes, until liquid has taken on flavor of onions. Remove from heat and strain liquid through tamis, pushing on onions with back of wooden spoon to extract as much liquid as possible. Reserve caramelized onion broth and discard mashed onions.

Make Soup

1. Slice remaining onions to same 1⁄2″ thickness. In same large pot on high heat, heat remaining oil. Add onions and cook, stirring. Brown them more quickly than first batch; just make sure you don’t burn them — stay close and stir often. Sprinkle in 1 tbsp of salt; it will help break down onions and release moisture.
2. After 15 to 20 minutes, lower heat to medium. Stir in butter until it melts, then sprinkle flour on top and stir until fully incorporated.
3. Deglaze with cognac, then wine and finally beer. Reduce liquid by half. Stir in caramelized Onion Stock, bring to a simmer, cover and simmer gently for 30 minutes, stirring once in a while. Stir in Worcestershire sauce and pepper. Taste for seasoning.
4. Preheat broiler, with rack in top position. Place 6 onion soup bowls on baking sheet and ladle onion soup into them, leaving space for croutons and cheese. Add handful of croutons to each bowl and top with 2 slices of Gruyère and 2 slices of Emmenthal. Broil until cheese is melted, caramelized and bubbly. Wait a few minutes before taking first bite, as soup will be nuclear hot.