Caramelized Onion Gruyère Cheese (Printable Version)

Sweet onions and melted Gruyère come together on golden toasted country bread for a rich melt.

# The Ingredients You'll Need:

→ Caramelized Onions

01 - 2 large yellow onions, thinly sliced
02 - 2 tablespoons unsalted butter
03 - 1 tablespoon olive oil
04 - 0.5 teaspoon salt
05 - 0.25 teaspoon freshly ground black pepper
06 - 1 teaspoon fresh thyme leaves (optional)
07 - 1 teaspoon balsamic vinegar (optional)

→ Sandwich

08 - 4 slices rustic country bread
09 - 4 ounces (115 grams) Gruyère cheese, grated
10 - 1 tablespoon unsalted butter, softened

# Step-by-Step Instructions:

01 - Melt butter with olive oil in a large skillet over medium-low heat. Add onions, salt, and pepper; cook, stirring occasionally, until deep golden and caramelized, about 25 to 30 minutes. Stir in thyme and balsamic vinegar if using, cook 1 minute longer. Remove from heat.
02 - Arrange bread slices on a workspace. Spread caramelized onions evenly over two slices, then top each with half the grated Gruyère. Close sandwiches with remaining bread slices.
03 - Spread softened butter on the exterior surfaces of each sandwich.
04 - Heat a nonstick skillet or griddle over medium heat. Place sandwiches in the pan and cook until golden brown and cheese is melted, about 3 to 4 minutes per side, pressing gently with a spatula for even toasting.
05 - Slice sandwiches in half and serve immediately.

# Additional Tips::

01 -
  • The way the sweet onions and nutty Gruyère melt together creates something far greater than the sum of its parts
  • Its fancy enough for dinner guests but simple enough for a solo Tuesday night
  • The caramelized onions can be made ahead and kept in the fridge for instant upgrade sandwiches all week
02 -
  • Low and slow is non negotiable for caramelized onions. High heat will burn them before they develop that deep sweetness.
  • Grating your own cheese makes a huge difference. Pre shredded cheese has anti caking agents that prevent smooth melting.
  • Letting the assembled sandwiches sit for a minute before grilling helps the bread bond with the filling.
03 -
  • Patience with the onions pays off. Rushing this step is the difference between good grilled cheese and great grilled cheese.
  • Mayonnaise can be mixed with the butter for an extra crispy exterior that browns more evenly.
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