Caramelized Onion Grilled Cheese (Printable Version)

Buttery bread with sweet caramelized onions and melted sharp white cheddar cheese. An indulgent, gooey comfort classic.

# 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

→ Seasonings

08 - Freshly ground black pepper to taste

# How to Make It:

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

# Expert Tips:

01 -
  • The caramelized onions add a deep, jammy sweetness that turns a simple grilled cheese into something you'll crave on repeat.
  • It comes together with pantry staples and a little patience, no fancy ingredients required.
  • The contrast between crispy, buttery bread and gooey, sharp cheddar is pure comfort in every bite.
  • It's flexible enough to make your own with different cheeses, herbs, or a swipe of mustard.
02 -
  • Don't rush the onions, they need a full 20 minutes of slow cooking to develop that deep sweetness and jammy texture.
  • Keep the heat on medium-low when grilling the sandwiches or the bread will burn before the cheese melts.
  • Grate your own cheese instead of using pre-shredded, it melts better and doesn't have the anti-caking agents that can make it grainy.
03 -
  • Use a cast iron skillet if you have one, it holds heat evenly and gives the bread an extra crispy crust.
  • Press the sandwich gently with the spatula while it cooks to help the cheese melt faster and create better contact with the pan.
  • If you're making more than two sandwiches, keep finished ones warm in a low oven while you cook the rest.
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