Caramelized Onion Grilled Cheese (Printer-friendly)

Golden-brown sourdough with sweet caramelized onions and sharp cheddar. A buttery, melted comfort classic.

# What You'll Need:

→ Bread & Dairy

01 - 4 slices sourdough or country bread
02 - 2 tablespoons unsalted butter, softened
03 - 4 ounces sharp white cheddar cheese, grated

→ Onions

04 - 2 large yellow onions, thinly sliced
05 - 1 tablespoon olive oil
06 - 1/2 teaspoon salt
07 - 1/2 teaspoon sugar

→ Seasonings

08 - Freshly ground black pepper to taste

# How to Make It:

01 - Heat olive oil in a large skillet over medium heat. Add the sliced onions and salt, stirring to coat evenly. Cook, stirring occasionally, for 20-25 minutes until deeply golden and caramelized. Add sugar halfway through cooking to enhance sweetness and browning.
02 - Remove onions from heat and set aside. Wipe out skillet if needed for sandwich preparation.
03 - Butter one side of each bread slice. Place two slices, buttered side down, on a clean surface. Top each with half the grated cheddar, then distribute caramelized onions evenly over the cheese. Sprinkle with black pepper. Cover with remaining bread slices, buttered side up.
04 - Heat skillet over medium-low heat. Place sandwiches in skillet and cook 3-4 minutes per side, pressing gently, until bread is crisp and golden and cheese is melted. Adjust heat as needed to prevent burning.
05 - Remove from pan and let rest for 2 minutes. Slice diagonally and serve hot.

# Expert Suggestions:

01 -
  • The onions cook down into a jammy sweetness that tastes like you spent all day in the kitchen, even though you didn't.
  • Sharp cheddar cuts through the richness in a way that keeps you coming back for another bite.
  • It's the kind of sandwich that makes you slow down and actually taste your food instead of inhaling it over the sink.
  • You can make the onions ahead and have them ready in the fridge whenever the craving hits.
02 -
  • Patience with the onions is everything; if you rush them over high heat they'll burn on the edges and stay raw in the center instead of turning sweet and jammy.
  • Softened butter spreads without tearing the bread, and cold butter will rip holes that leak cheese and make uneven browning.
  • Medium-low heat on the skillet gives the cheese time to melt before the bread burns, so don't crank it up even if you're hungry.
03 -
  • Grate your own cheese instead of buying pre-shredded; it melts smoother and doesn't have the anti-caking agents that make it grainy.
  • Press the sandwich gently with your spatula while it cooks to help the cheese melt into the onions and create better contact with the pan for even browning.
  • Let the sandwich rest for a full 2 minutes after cooking so the cheese firms up just enough that it doesn't all slide out when you cut into it.
Go Back