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Double Decker French Onion Patty Melt Recipe
Ben Carraoli

Double Decker French Onion Patty Melt Recipe

I made this Double Decker French Onion Patty Melt Recipe last weekend, and honestly—it was an instant hit. The flavor reminded me of a cozy bowl of French onion soup but packed between layers of crispy toast and melty Gruyere. I’m a big fan of hearty meals, and this one definitely checks all the boxes. It’s satisfying, cheesy, meaty, and totally unforgettable.
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Prep Time 10 minutes
Cook Time 34 minutes
Total Time 44 minutes
Servings: 4
Course: Dinner
Calories: 1520
Ingredients Method

Ingredients
  

  • For the Patty Melt
  • 3 tablespoons butter – Helps caramelize the onions to a rich golden brown.
  • 3 yellow onions thinly sliced – Sweet and perfect for that classic French onion flavor.
  • 2 pounds ground beef – Use 80/20 for juicy patties that don’t dry out.
  • 1 tablespoon ketchup – Adds just a hint of sweetness and umami.
  • ½ teaspoon garlic powder – For subtle aromatic depth.
  • 1 teaspoon salt – Essential for seasoning the meat properly.
  • ½ teaspoon pepper – A touch of sharpness to balance the sweetness.
  • 2 cups Gruyere cheese shredded – Melts beautifully and mimics the essence of French onion soup.
  • 12 slices Texas toast – Thick and sturdy enough to handle all those layers.
  • 8 teaspoons mayonnaise – Creates a golden crispy crust when grilled.
  • For the Aioli Spread
  • ⅓ cup mayonnaise – Creamy base for the aioli.
  • 1 tablespoon lemon juice – Adds brightness and balance.
  • 1 teaspoon pepper – A peppery punch for flavor contrast.
  • 1 tablespoon minced garlic about 3 cloves – Bold and aromatic.
  • 1 teaspoon fresh parsley – Adds color and freshness.
  • 1 tablespoon ketchup – Brings a tangy sweetness.

Method
 

  1. Start by melting butter in a skillet over medium-low heat. Add the thinly sliced onions and stir often, letting them cook slowly for about 15–20 minutes. Add small amounts of water if they begin to stick. Once caramelized, remove the onions from heat and cover to keep warm.
  2. In a large bowl, combine ground beef, ketchup, garlic powder, salt, and pepper. Mix gently—overmixing can make the patties tough. Shape into 8 square patties slightly larger than your bread. Heat a skillet over medium-high and cook each patty for 1–2 minutes per side. Set them aside.
  3. Mix mayo, lemon juice, pepper, minced garlic, parsley, and ketchup in a small bowl. Stir well until smooth. This creamy spread adds big flavor and a hint of zing.
  4. Lightly toast 4 slices of the Texas toast and set them aside. These will go in the center of the sandwich stack.
  5. On 4 untoasted slices of bread, layer cheese, one cooked beef patty, caramelized onions, a toasted bread slice with aioli on both sides, more cheese, a second beef patty, extra onions, and top with another slice of bread. Spread mayo on the top slice.
  6. Heat the skillet again and place each sandwich mayo-side down. Place a heavy pan or press on top and grill for about 3 minutes. Remove the weight, spread mayo on the top slice, and carefully flip. Cook the other side for another 3 minutes until golden brown and crispy.