Sheet Pan Grilled Cheese

Standing over a frying pan to make a single grilled cheese sandwich isn’t too demanding, but cooking multiple sandwiches for a family can quickly become a chore. This method simplifies the process: assemble the sandwiches, place them on a parchment-lined sheet pan on the bottom rack of the oven, sprinkle a little grated cheese for extra crispy bits, and flip them halfway through.

In this version, I’ve made it dinner-worthy by adding caramelized onions. Serve these sandwiches with soup or salad for a complete meal — this will become part of your regular dinner rotation, I promise.

Ingredients:
¼ cup unsalted or salted butter, softened
8 slices sandwich bread
1 to 1½ cups (4 to 6 ounces) grated Gruyère (or substitute a good melting cheese like cheddar, Swiss, or American)
½ cup (about 2 ounces) grated Parmesan
4 medium yellow onions, thinly sliced
2 tablespoons olive oil
Salt and pepper to taste

Preparation:
In a large pan over low heat, sauté the onions in olive oil until golden and very soft, about 30 to 45 minutes. (See note.)

Set a rack in the oven to the bottom position and preheat to 400°F.

Line a sheet-pan with parchment paper. Spread butter on 4 slices of bread and place them buttered side down on the sheet-pan, then top each with grated Gruyère. Pile the caramelized onions on top of the cheese, then cover with the remaining bread slices.

Place the sandwiches on the sheet pan and bake for 7 to 9 minutes, until the bottoms are golden. Remove from the oven and sprinkle the Parmesan onto the empty part of the sheet pan, spreading it out so it isn’t in a solid pile. Flip the sandwiches onto the Parmesan and return to the oven. Bake for another 5 to 7 minutes, until the Parmesan is crispy and golden.

Note: The onions can be prepared in advance and stored in the fridge for 3 to 4 days.