Caramelized Onion Gruyère Cheese (Printable)

Sweet caramelized onions paired with nutty Gruyère layered on buttery, toasted bread for a savory melt.

# Ingredient List:

→ Caramelized Onions

01 - 2 medium yellow onions, thinly sliced
02 - 2 tablespoons unsalted butter
03 - 1/2 teaspoon kosher salt
04 - 1/4 teaspoon freshly ground black pepper
05 - 1/2 teaspoon sugar (optional)
06 - 1 teaspoon balsamic vinegar (optional)

→ Sandwich

07 - 4 slices rustic sourdough or country bread
08 - 2 tablespoons unsalted butter, softened
09 - 5 ounces Gruyère cheese, grated
10 - Caramelized onions (prepared)

# How-To Steps:

01 - Melt 2 tablespoons unsalted butter in a large skillet over medium-low heat. Add thinly sliced onions, kosher salt, and black pepper. Cook, stirring occasionally, for 25 to 30 minutes until onions reach a deep golden color. Optionally, stir in sugar and balsamic vinegar, then cook for an additional 2 to 3 minutes. Remove from heat.
02 - Butter one side of each bread slice with softened butter. Arrange two slices butter-side down on a flat surface. Evenly distribute half the grated Gruyère over them, then spoon the caramelized onions atop the cheese. Sprinkle remaining Gruyère over onions and close each sandwich with a buttered slice, butter-side up.
03 - Heat a nonstick skillet or griddle over medium heat. Place sandwiches in the skillet and cook approximately 3 to 4 minutes per side, pressing gently with a spatula, until bread is golden and cheese melts. Lower heat if bread browns too quickly before cheese melts.
04 - Slice sandwiches and serve immediately, optionally accompanied by a crisp green salad or tomato soup.

# Expert Advice:

01 -
  • Grilled cheese that tastes like it came from a French bistro
  • The onions become candy, which balances the sharp cheese perfectly
  • Ready in under an hour but feels like a slow Sunday meal
02 -
  • Do not rush the onions, they need time to develop that deep sweetness
  • Low and slow is better than high and fast for both onions and grilling
  • Covering the pan for the last minute of grilling helps the cheese melt completely
03 -
  • Grate your own cheese instead of buying pre grated for better melting
  • Use a cast iron skillet for the most even heat distribution
  • Butter the bread all the way to the edges so every corner gets golden
Go Back