Caramelized Onion & Gruyère Grilled Cheese (Printable Version)

Slow-cooked caramelized onions meet nutty Gruyère cheese between crispy, golden country bread for an elegant comfort classic.

# 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

# Step-by-Step Instructions:

01 - In a large skillet over medium-low heat, melt butter with olive oil. Add sliced onions, salt, and pepper. Cook, stirring occasionally, until deeply golden and caramelized, approximately 25-30 minutes. 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. Place remaining bread slices on top to close 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 pan and cook until golden brown with melted cheese, approximately 3-4 minutes per side. Press gently with spatula to ensure even toasting.
05 - Slice sandwiches in half and serve immediately.

# Expert Advice:

01 -
  • The onions transform into something jammy and sweet that balances perfectly with sharp Gruyère
  • Country bread develops this incredible shattering crunch while staying tender inside
  • It takes patience but the result is miles beyond any diner grilled cheese you have ever had
02 -
  • Rushing the onions is the mistake everyone makes. Low and slow gives you sweetness while high heat just burns them.
  • Grating your own cheese makes an enormous difference in how smoothly it melts compared to the pre shredded stuff.
03 -
  • Use a cast iron skillet for the most even heat distribution and best crust development
  • If the cheese is not melting but the bread is getting too dark, tent the pan with foil for a minute
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