Caramelized Onion Grilled Cheese (Printable Version)

Buttery bread layered with sweet caramelized onions and sharp white cheddar. A simple yet elegant comfort sandwich perfect for lunch.

# What You 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, optional

→ Seasonings

08 - Freshly ground black pepper to taste

# How-To Steps:

01 - Heat olive oil in a large skillet over medium heat. Add sliced onions and salt, stirring to coat. Cook, stirring occasionally, for 20 to 25 minutes until deeply golden and caramelized. Add sugar halfway through if desired to enhance sweetness and browning.
02 - Remove caramelized onions from heat and set aside. Wipe out skillet if needed.
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 pile 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 to 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 sandwiches from pan, let rest 2 minutes, slice diagonally, and serve hot.

# Expert Advice:

01 -
  • The onions turn impossibly sweet and jammy without any fancy ingredients, just patience and a little olive oil.
  • Sharp cheddar cuts through the sweetness in a way that makes every bite feel balanced, not cloying.
  • It tastes like something from a cafe but costs almost nothing to make at home.
  • The buttery, crisp bread shatters when you bite down, then melts into all that cheese and onion.
02 -
  • If the onions start to stick or look dry, add a splash of water and scrape up the browned bits, they add so much flavor.
  • Don't rush the caramelizing, low and slow is the only way to get that deep sweetness without bitterness.
  • Press the sandwich gently while it cooks but don't smash it flat, you want the cheese to melt without squeezing out.
03 -
  • Let the butter come to room temperature so it spreads evenly without tearing the bread.
  • Grate your own cheese instead of buying pre shredded, it melts smoother and tastes fresher.
  • If you're making multiple sandwiches, keep the finished ones warm in a low oven while you cook the rest.
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