For best results, use a heavy-bottomed pot to ensure even caramelization of the onions. Do not rush the caramelization process; this is crucial for flavor. If you don't have Gruyère, Swiss, Provolone, or Emmental cheese are good substitutes. A splash of dry white wine or sherry can be added after caramelizing the onions for extra depth, deglazing the pot.
Keyword French onion soup, Ree Drummond, comfort food, cheesy soup, beef broth, caramelized onions, classic French recipe