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This gourmet grilled cheese requires a little prep work but is easy to assemble. Much like any grilled cheese sandwich, you can change up the bread type and the cheese type to make it your own.

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grilled cheese sandwich sliced in half diagonally and stacked on a white plate. There is cheese and bread in the background.

Ingredients

Bread - Make sure it's a good sturdy bread to hold up to the ingredients
Cheese - Gouda
Vegetables - Mushrooms, Onions, Spinach or Arugula
Condiments - Butter, Olive oil, Balsamic Vinegar, Salt & Pepper

Top Tip

Prepare the caramelized onions & mushrooms ahead of time. They can be stored in the refrigerator until ready to use.

Related: How To Make Caramelized Onions

Variations

This hearty grilled cheese sandwich is pretty much perfection as I've prepared it but if you don't have the ingredients or you'd like to change it up, here are some suggestions.

Cheese suggestions for grilled cheese - Gruyere, Fontina, White Cheddar, Mozzarella
Bread alternatives - Scali bread, ciabatta rolls, sourdough, peasant bread

grilled cheese cut in half with onions, mushrooms and spinach hanging out. The sandwich is on a white plate.

What to serve with grilled cheese

Sweet Potato Cubes
Soups
French Fries
Salad

Love cheesy sandwiches? Visit this 21 Cheesy Stuffed Burgers collection!

Printable Recipe Card

cooked grilled cheese, cut in half, each half stacked on each other on a white plate

Caramelized Onion and Mushroom Grilled Cheese

foodyschmoody

A grown-up grilled cheese featuring caramelized onions, mushrooms and cheese served on a hearty bread. A tasty grilled sandwich for lunch or dinner.

5 from 1 vote

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Prep Time 20

Cook Time 5

Total Time 25

Course lunch, Main Course

Cuisine American

Servings sandwiches

Calories 695 kcal

Ingredients

1 Tablespoon butter
1 Tablespoon olive oil
2 Large sweet onions sliced thinly
4 Ounces baby bella mushrooms sliced
1½ Teaspoon balsamic vinegar
¼ Teaspoon salt
⅛ Teaspoon black pepper freshly cracked
4 Ounces or 4 slices Gouda
1½ Cup spinach or spinach/arugula blend
2 Tablespoon butter softened
4 Slices bread Thick, seeded slices work great

Instructions

Melt butter in a large non stick skillet with olive oil, over high heat. Add onions and mushrooms and cook 3-4 minutes. After 3-4 minutes, knock the heat down to medium low and let them cook about 15 minutes, only stirring two or three times during this time. After 15 minutes the onions should be softened and gaining caramelization. Stir in the balsamic vinegar, salt and pepper. Cook 5 minutes more. Set aside until ready to use.
Spread the softened butter on one side of each slice of bread.
Place two buttered slices of bread, butter side down on a cutting board or wax paper to assemble. Layer ingredients on bread in this order:
1 oz (or 1 slice) Gouda, onions & mushrooms, half the spinach, another slice or ounce of Gouda. Top with bread, butter side up.
Heat non stick skillet over medium/high heat. Add sandwiches, one at a time to skillet. Cook on each side 3-4 minutes, until bread is toasty and cheese is melted.
Serve immediately.

Nutrition

Calories: 695kcalCarbohydrates: 57gProtein: 25gFat: 43gSaturated Fat: 22gPolyunsaturated Fat: 3gMonounsaturated Fat: 14gTrans Fat: 1gCholesterol: 110mgSodium: 1204mgPotassium: 932mgFiber: 6gSugar: 23gVitamin A: 2959IUVitamin C: 22mgCalcium: 572mgIron: 4mg

Keyword grilled cheese, grilled sandwich, sandwich, vegetarian

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