French Onion Grilled Cheese (Print Version)
Savory sandwich with caramelized onions, melty Gruyère, and golden crisp bread; a cozy vegetarian main.
# What You’ll Need:
→ Caramelized Onions
01 - 2 tablespoons unsalted butter
02 - 1 large yellow onion, thinly sliced
03 - 1 teaspoon fresh thyme leaves or 1/2 teaspoon dried thyme
04 - 1/4 teaspoon salt
05 - 1/8 teaspoon freshly ground black pepper
06 - 1 teaspoon balsamic vinegar
→ Sandwiches
07 - 4 slices sourdough bread or country bread
08 - 1 1/2 cups shredded Gruyère cheese
09 - 2 tablespoons mayonnaise or softened butter, for spreading
10 - 1/2 teaspoon Dijon mustard, optional
# How to Make It:
01 - Melt unsalted butter in a skillet over medium heat. Add sliced onions, thyme, salt, and pepper. Cook, stirring frequently, until onions are deeply caramelized and golden brown, about 18 to 20 minutes. Add balsamic vinegar and cook 1 minute more. Set aside.
02 - Lay out bread slices and spread mayonnaise or softened butter on one side of each slice.
03 - On the unbuttered side of two bread slices, spread Dijon mustard if using. Top each with half of the caramelized onions and half of the shredded Gruyère cheese. Close the sandwiches with remaining bread slices, ensuring the buttered side faces outward.
04 - Heat a nonstick skillet or griddle over medium-low heat. Place sandwiches in the pan and cook until the bread is golden and cheese is melted, about 4 to 5 minutes per side. Press gently with a spatula for even crust development.
05 - Slice the sandwiches and serve immediately while warm.
# Additional Tips::
01 -
- Uses easy to find ingredients and a single skillet
- Ready in about forty minutes and simple to master
- Perfect balance of sweet onions and savory melted cheese
- Vegetarian and satisfying enough for lunch or dinner
02 -
- High in protein and keeps you full
- Caramelized onions freeze beautifully for easy make ahead
- A creative twist on a café classic that always impresses
03 -
- Use low and slow heat for onion caramelization patience pays off
- Spread the cheese evenly to the outer edge for the best melt and cheese pull
- A heavy bottomed pan ensures a crisp crust without burning