Caramelized Onion Grilled Cheese (Printable Version)

Buttery sourdough with sweet caramelized onions and sharp cheddar, grilled to golden perfection.

# What You'll Need:

→ Bread & Dairy

01 - 4 slices sourdough or country bread
02 - 2 tablespoons unsalted butter, softened
03 - 4 oz 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)

→ Extras

08 - Freshly ground black pepper, to taste

# Steps to Follow:

01 - Heat olive oil in a large skillet over medium heat. Add sliced onions and salt, stirring to coat. Cook for 20-25 minutes until deeply golden, stirring occasionally. Add sugar halfway through to enhance caramelization if desired.
02 - Remove onions from heat and set aside. Wipe skillet if needed. Butter one side of each bread slice.
03 - Place two slices of bread, buttered side down, on a flat surface. Distribute grated cheddar evenly over them, then layer caramelized onions. Sprinkle with black pepper and cover with remaining bread slices, buttered side up.
04 - Heat skillet over medium-low heat. Cook sandwiches for 3-4 minutes per side, pressing gently, until bread is golden and cheese is melted. Adjust heat to prevent burning.
05 - Remove sandwiches from pan, let rest 2 minutes. Slice and serve warm.

# Additional Tips::

01 -
  • The caramelized onions are so jammy and sweet they taste almost like a secret ingredient nobody can quite identify.
  • It's impossibly easy but tastes like you spent all day cooking.
  • One sandwich satisfies in a way that most comfort foods don't—it's balanced, rich, and somehow still feels light.
02 -
  • Don't rush the onions; caramelization is about low heat and time, not high heat and speed—rushing them gives you brown onions instead of caramelized ones.
  • Press the sandwich gently while it cooks so the cheese actually melts and bonds with the bread instead of staying in separate layers.
03 -
  • Keep your skillet at medium-low heat so the outside of the bread crisps before the inside gets too hot and the cheese fails to melt evenly.
  • If your first sandwich browns too fast, lower the heat—every skillet is different, and adjusting mid-cook is the difference between perfect and burnt.
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