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Caramelized Onion Grilled Cheese – A Gourmet Twist on a Classic


  • Author: isabil
  • Total Time: 50 minutes
  • Yield: 2 servings 1x

Description

This Caramelized Onion Grilled Cheese is the perfect blend of sweet, savory, and crispy. A gourmet twist on a classic comfort food!


Ingredients

Scale

For the Caramelized Onions:

  • 2 large yellow or sweet onions, thinly sliced
  • 2 tablespoons butter
  • 1 tablespoon olive oil
  • ½ teaspoon salt
  • ½ teaspoon sugar (optional)
  • 1 teaspoon balsamic vinegar (optional, for added depth)

For the Sandwich:

  • 2 slices of thick-cut bread (sourdough, brioche, or artisan bread)
  • 2 tablespoons butter, softened
  • ½ cup grated or sliced cheese (Gruyère, sharp cheddar, Swiss, or mozzarella)
  • 1 teaspoon Dijon mustard (optional, for a tangy kick)
  • 1 teaspoon mayonnaise (for extra crispiness, optional)
  • Fresh thyme or rosemary (optional, for extra flavor)

Instructions

  • Caramelize the Onions:

    • Heat butter and olive oil in a skillet over medium-low heat.
    • Add thinly sliced onions, stir to coat, and season with salt and sugar.
    • Cook slowly for 30-40 minutes, stirring occasionally, until onions are deep golden brown.
    • Stir in balsamic vinegar (optional) and cook for another 2 minutes.
    • Remove from heat and set aside.
  • Assemble the Sandwich:

    • Butter one side of each bread slice.
    • Spread Dijon mustard or mayonnaise (if using) on the unbuttered side.
    • Layer cheese on one slice of bread.
    • Add a generous portion of caramelized onions and sprinkle with thyme or rosemary (if using).
    • Top with the second slice of bread, buttered side facing out.
  • Cook the Sandwich:

    • Heat a skillet or griddle over medium-low heat.
    • Place the sandwich in the skillet and cook for 3-4 minutes per side, pressing gently with a spatula.
    • Flip carefully and continue cooking until the bread is golden brown and crispy, and the cheese is melted.
  • Serve and Enjoy:

    • Remove from heat, let sit for 1 minute, then slice and serve immediately.
    • Pair with tomato soup, fries, or a fresh salad for a complete meal.

Notes

  • Cook onions low and slow for the best caramelization.
  • Use butter and olive oil together for rich flavor and even cooking.
  • Gruyère, sharp cheddar, and gouda work best for a gooey texture.
  • Press gently while cooking for even crispiness and melting.
  • Store caramelized onions in an airtight container for up to 5 days for easy meal prep.
  • Prep Time: 10minutes
  • Cook Time: 40 minutes