Caramelized Onion Grilled Cheese (Printable Version)

Buttery bread layered with sweet caramelized onions and sharp white cheddar for an elevated comfort sandwich.

# Ingredient List:

→ 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

→ Seasoning

08 - Freshly ground black pepper to taste

# Directions:

01 - Heat olive oil in a large skillet over medium heat. Add sliced onions and salt, stirring to coat evenly. 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 onions from heat and transfer to a bowl. Wipe out skillet if needed.
03 - Butter one side of each bread slice. Place two slices, buttered side down, on a clean work surface.
04 - Top each bread slice 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.
05 - Heat skillet over medium-low heat. Place assembled sandwiches in skillet and cook 3 to 4 minutes per side, pressing gently, until bread is crisp and golden and cheese is fully melted. Adjust heat as needed to prevent burning.
06 - Remove sandwiches from pan and let rest for 2 minutes. Slice diagonally and serve hot.

# Expert Tips:

01 -
  • The onions turn so sweet and jammy, they taste like they've been cooking in butter for hours, because they kind of have.
  • Sharp white cheddar cuts through the sweetness with a tangy bite that keeps each bite interesting instead of cloying.
  • It's fancy enough to serve friends but simple enough to make on a rainy Tuesday when you need something warm and comforting.
  • Leftovers reheat beautifully in a skillet, crisping right back up without getting soggy.
02 -
  • Don't rush the onions on high heat or they'll burn on the edges and stay raw in the middle, which tastes bitter and unpleasant.
  • Use medium-low heat when grilling the sandwich so the bread crisps at the same rate the cheese melts, otherwise you'll have burnt bread and cold cheese.
  • Grate your own cheese instead of buying pre-shredded, it melts so much smoother and doesn't have that weird grainy texture.
  • Let the sandwich rest after cooking or all the cheese will slide out the second you cut into it.
03 -
  • Make a big batch of caramelized onions and freeze them in small portions, they reheat perfectly and save you 25 minutes next time.
  • Press the sandwich gently with a spatula while it cooks to help the cheese melt faster and get better contact with the pan for crispier bread.
  • Use a lid for the first minute or two of cooking on each side to trap heat and melt the cheese faster without burning the bread.
  • If you're making multiple sandwiches, keep the finished ones warm in a low oven while you cook the rest.
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