Grilled Cheese With Caramelized Onion Sandwiches

Grilled cheese sandwich with caramelized onion

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Prep: 10 mins
Cook: 30 mins
Total: 40 mins
Servings: 4 servings
Nutrition Facts (per serving)
443 Calories
35g Fat
18g Carbs
15g Protein
Show Full Nutrition Label Hide Full Nutrition Label
Nutrition Facts
Servings: 4
Amount per serving
Calories 443
% Daily Value*
Total Fat 35g 45%
Saturated Fat 18g 90%
Cholesterol 85mg 28%
Sodium 380mg 17%
Total Carbohydrate 18g 6%
Dietary Fiber 2g 6%
Protein 15g
Calcium 463mg 36%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

These delicious grilled cheese sandwiches with caramelized onions are easy to make, especially if you make the caramelized onions ahead of time. Make a batch and keep in the fridge for 3 to 4 days. You can add them to everything from meatloaf to scrambled eggs. We like to add sliced garlic to the onions during the last 5 minutes of cooking time for another layer of flavor.

There's nothing better or more satisfying, or simpler to make than a grilled cheese sandwich or any hot sandwich. These recipes can be changed any way you'd like. Use a different bread, a different cheese, more cheeses, or add veggies such as sliced tomatoes, sautéed bell peppers, or spinach or other greens. You could also add some sautéed apples or pears for a sandwich reminiscent of fall. Add some crisply cooked bacon or thinly sliced ham for a fabulous variation. If you change the recipe, write down the changes so you can reproduce your masterpiece.

These easy sandwiches can be served with nothing but a cold glass of milk, but you could add a green salad or a fruit salad for a complete meal.


  • 2 onions (chopped)
  • 2 tablespoons olive oil
  • 1 tablespoon butter
  • 1 tablespoon brown sugar
  • 1/2 teaspoon salt
  • 1/8 teaspoon pepper
  • 8 thin slices Gruyere or Havarti cheese
  • 8 slices whole-wheat bread
  • 1/4 cup butter (softened)

Steps to Make It

  1. Combine the onions, olive oil, and butter in a heavy skillet. Sauté over medium heat, stirring frequently until onions start to brown, about 10 minutes.

  2. Reduce the heat to low and cook, stirring occasionally, until onions become golden brown, about 15 to 25 minutes longer. Toward the end of the cooking time, watch the onions carefully and stir more often so they don't burn. Sprinkle the onions with sugar, salt, and pepper, cook for another 2 to 3 minutes, and remove from the heat.

  3.  Let the mixture cool, then store, covered, in the fridge for 3 to 4 days. You can freeze caramelized onions for longer storage, up to 3 months. To thaw, let them stand in the fridge overnight.

  4. To make sandwiches, place the bread on a work surface. Top four slices of the bread with a slice of cheese, then spread with a few spoonfuls of the caramelized onion mixture. Top with another slice of cheese. Top with remaining slices of bread to make four sandwiches.

  5. Spread the outsides of the sandwiches with the softened butter. Grill sandwiches, covered, until toasted, turning once over medium heat, or cook them on a panini grill or dual contact indoor grill. Serve immediately.