Caramelized Onion & Gruyère Grilled Cheese (Printable)

Sweet caramelized onions and nutty Gruyère melted between crispy country bread slices. Pure comfort in every bite.

# Ingredient List:

→ Caramelized Onions

01 - 2 large yellow onions, thinly sliced
02 - 2 tablespoons unsalted butter
03 - 1 tablespoon olive oil
04 - 1/2 teaspoon salt
05 - 1/4 teaspoon freshly ground black pepper
06 - 1 teaspoon fresh thyme leaves
07 - 1 teaspoon balsamic vinegar

→ Sandwiches

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

# Directions:

01 - In a large skillet over medium-low heat, melt butter with olive oil. Add sliced onions, salt, and pepper. Cook, stirring occasionally, for 25 to 30 minutes until deeply golden and caramelized. Stir in thyme and balsamic vinegar, then cook 1 minute longer. Remove from heat.
02 - Lay out bread slices. Evenly distribute caramelized onions on two slices. Top each with half of the grated Gruyère cheese. Place remaining bread slices on top to close the sandwiches.
03 - Spread softened butter evenly on the outside of each sandwich.
04 - Heat a non-stick skillet or griddle over medium heat. Place sandwiches in the pan and cook for 3 to 4 minutes per side until golden brown and cheese is melted. Press gently with a spatula to ensure even toasting.
05 - Slice sandwiches in half and serve immediately.

# Expert Suggestions:

01 -
  • The way the sweet onions balance against the sharp, nutty Gruyère creates this incredible depth that feels restaurant fancy but comes together in under an hour
  • Once you master caramelized onions, you will want to put them on everything from burgers to pasta to pizza
02 -
  • Low and slow is absolutely essential for caramelizing onions. If you try to rush this process over high heat, the onions will burn and turn bitter instead of developing that wonderful sweetness
  • Grating the cheese yourself instead of buying pre shredded makes a huge difference in how smoothly and evenly it melts
03 -
  • Patience with the onions is the difference between good and unforgettable. They will look like they are taking forever to cook, then suddenly transform into something incredible
  • Let the sandwiches rest for just one minute after cutting so the cheese has a moment to set slightly and does not ooze out completely
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