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Swiss Mushroom Melt Sandwich

Irresistible Swiss Mushroom Melt Sandwich You’ll Crave

This Swiss Mushroom Melt Sandwich is a quick, vegetarian delight with sautéed mushrooms, caramelized onions, and Swiss cheese, all in crunchy sourdough.
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Prep Time 15 minutes
Cook Time 30 minutes
Total Time 45 minutes
Servings: 2 sandwiches
Course: Lunch
Cuisine: American
Calories: 550
Ingredients Equipment Method Nutrition Notes

Ingredients
  

For the Caramelized Onions
  • 2 whole yellow onions Opt for sweet onions if desired
  • 2 tablespoons olive oil Can substitute with vegetable oil
  • 1 tablespoon butter Use plant-based butter for a vegan variant
  • 1 tablespoon brown sugar Can be replaced with maple syrup
  • 1 tablespoon balsamic vinegar Red wine vinegar is a potential substitute
  • salt and pepper Essential seasonings for enhancing all flavors
For the Mushroom Filling
  • 8 ounces cremini mushrooms Button mushrooms can be used as an alternative
  • 2 cloves garlic Garlic powder is an acceptable replacement
  • 1/4 cup dry white wine Stock or additional broth can be used for a non-alcoholic option
  • 1 teaspoon fresh thyme Dried thyme is a suitable substitute
For the Sandwich Assembly
  • 4 slices sourdough bread Whole grain or gluten-free bread can be used
  • 4 slices Swiss cheese Gruyère or provolone can also work well
  • 2 tablespoons softened butter Can substitute with olive oil for a lighter option
  • 1 tablespoon Dijon mustard Yellow mustard can be a substitute

Equipment

  • skillet
  • cutting board
  • Knife

Method
 

Preparation
  1. Peel and thinly slice the yellow onions. Heat a skillet over medium-low heat, add olive oil and butter, and once melted, add onions. Cook for about 30-45 minutes until golden brown.
  2. Add brown sugar and balsamic vinegar to the caramelized onions. Season with salt and pepper, and continue cooking for another 5 minutes until glossy.
  3. In the same skillet, add another tablespoon of olive oil and sliced cremini mushrooms. Cook for 8-10 minutes until brown, then add minced garlic and thyme.
  4. If desired, deglaze the pan with dry white wine, scraping the bottom. Cook for about 2-3 minutes, then return the mushrooms to the pan and season to taste.
  5. Butter one side of each slice of sourdough. Spread Dijon mustard on the unbuttered sides of two slices, and layer with Swiss cheese, caramelized onions, and sautéed mushrooms.
  6. Heat a skillet over medium-low heat and place the assembled sandwich in. Cook until golden brown on one side, then flip and repeat for the other side.
  7. Once both sides are golden brown and cheese has melted, remove from skillet, cut in half, and serve immediately.

Nutrition

Serving: 1sandwichCalories: 550kcalCarbohydrates: 40gProtein: 20gFat: 30gSaturated Fat: 15gPolyunsaturated Fat: 2gMonounsaturated Fat: 5gCholesterol: 60mgSodium: 800mgPotassium: 600mgFiber: 4gSugar: 6gVitamin A: 10IUVitamin C: 2mgCalcium: 30mgIron: 10mg

Notes

Use freshly grated Swiss cheese for better melting properties. Avoid storing sandwiches at room temperature for safety.

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