Swiss Mushroom Melt Sandwich Recipe

Introduction

The Swiss Mushroom Melt Sandwich is a comforting, flavorful treat featuring sweet caramelized onions, savory sautéed mushrooms, and melted Swiss cheese on toasted sourdough. It’s perfect for a satisfying lunch or a cozy dinner that feels a little special without much fuss.

Ingredients

• 2 large yellow onions, thinly sliced
• 2 tablespoons olive oil (for onions)
• 1 tablespoon butter (for onions)
• 1 teaspoon brown sugar
• 1/2 teaspoon balsamic vinegar
• Salt and freshly ground black pepper to taste
• 1 pound cremini mushrooms, sliced
• 2 tablespoons olive oil (for mushrooms)
• 2 cloves garlic, minced
• 1/4 cup dry white wine (optional)
• 1 tablespoon fresh thyme leaves
• 4 slices sourdough bread (or your favorite bread)
• 4 ounces Swiss cheese, thinly sliced
• 2 tablespoons butter, softened (for assembling)
• 1 tablespoon Dijon mustard (optional)

Instructions

1. Step 1: Peel and thinly slice the yellow onions. Heat olive oil and butter in a large skillet over medium-low heat. Add the onions and stir to coat evenly.
2. Step 2: Cook the onions slowly for 30-45 minutes, stirring occasionally, until deep golden brown and very soft. If they brown too fast, lower the heat to prevent burning.
3. Step 3: Stir in the brown sugar and balsamic vinegar. Cook for 2-3 minutes until the sugar dissolves and the vinegar is absorbed. Season with salt and pepper, then remove from heat and set aside.
4. Step 4: Clean and slice the mushrooms. In the same skillet, heat olive oil over medium-high heat. Add the mushrooms and cook, stirring occasionally, for 8-10 minutes until browned and softened. Avoid overcrowding the pan.
5. Step 5: Add minced garlic and thyme leaves to the mushrooms. Cook for 1 minute until fragrant, stirring constantly to prevent burning.
6. Step 6: If using, pour in white wine and scrape the browned bits from the pan. Let the wine reduce for a couple of minutes until nearly evaporated. Season mushrooms with salt and pepper, then remove from heat and set aside.
7. Step 7: Lightly butter one side of each bread slice. Optional: Spread Dijon mustard on the unbuttered side of two slices.
8. Step 8: Place the bread slices buttered-side down on a clean skillet over medium-low heat. Layer half the Swiss cheese on each slice.
9. Step 9: Top cheese on one slice with half the caramelized onions and mushrooms. Repeat on the other slice. Cook 3-5 minutes per side until cheese melts and bread is golden brown. Cover skillet to speed melting if desired.
10. Step 10: Remove sandwiches carefully, place one slice atop the other to make a complete sandwich. Cut in half and serve immediately.

Tips & Variations

• Use high-quality sourdough and fresh mushrooms for the best flavor.
• Be patient when caramelizing onions; the slow cooking brings out their natural sweetness.
• Season onions and mushrooms generously with salt and pepper, tasting as you go.
• Try other cheeses like Gruyere, provolone, or sharp cheddar for a different twist.
• Add a sauce such as garlic aioli, pesto, or balsamic glaze for extra flavor complexity.

Storage

Store leftover sandwiches wrapped tightly in the refrigerator for up to 2 days. Reheat gently in a skillet over low heat or in a toaster oven to preserve the sandwich’s texture and melt the cheese evenly. Avoid microwaving as it can make the bread soggy.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I make the caramelized onions and mushrooms ahead of time?

Yes, both can be prepared in advance and stored separately in airtight containers in the refrigerator for up to 3 days. Reheat gently before assembling the sandwich.

What if I don’t have white wine for the mushrooms?

You can skip the wine or substitute with a splash of vegetable or chicken broth. The wine adds depth but isn’t essential.

Swiss Mushroom Melt Sandwich Recipe

Print Recipe

★★★★★

4.5 from 58 reviews

A delicious Swiss Mushroom Melt Sandwich featuring slow-cooked caramelized onions, sautéed cremini mushrooms with garlic and thyme, and melted Swiss cheese on buttery toasted sourdough bread. This savory sandwich combines rich, earthy flavors and a perfect gooey melt, ideal for a comforting lunch or dinner.

• Author: Ella
• Prep Time: 15 minutes
• Cook Time: 50 minutes
• Total Time: 1 hour 5 minutes
• Yield: 2 sandwiches 1x
• Category: Sandwich
• Method: Stovetop
• Cuisine: American
• Diet: Vegetarian

Ingredients

Scale 1x2x3x

For the Caramelized Onions:

• 2 large yellow onions, thinly sliced
• 2 tablespoons olive oil
• 1 tablespoon butter
• 1 teaspoon brown sugar
• 1/2 teaspoon balsamic vinegar
• Salt and freshly ground black pepper to taste

For the Sautéed Mushrooms:

• 1 pound cremini mushrooms, sliced
• 2 tablespoons olive oil
• 2 cloves garlic, minced
• 1/4 cup dry white wine (optional, but recommended)
• 1 tablespoon fresh thyme leaves
• Salt and freshly ground black pepper to taste

For the Sandwich Assembly:

• 4 slices sourdough bread (or your favorite bread)
• 4 ounces Swiss cheese, thinly sliced
• 2 tablespoons butter, softened
• 1 tablespoon Dijon mustard (optional)

Instructions

1. Caramelize the Onions: Peel and thinly slice the yellow onions. Heat olive oil and butter in a large skillet over medium-low heat. Add onions and stir to coat. Cook slowly for 30-45 minutes, stirring occasionally, until deep golden brown and soft. Stir in brown sugar and balsamic vinegar, cooking 2-3 more minutes until absorbed. Season with salt and pepper, then set aside.
2. Sauté the Mushrooms: Clean and slice cremini mushrooms. In the same skillet, heat olive oil over medium-high heat. Add mushrooms and cook, stirring occasionally, until browned and softened (8-10 minutes). Add minced garlic and thyme; cook for 1 minute. Deglaze pan with white wine if using and let it reduce nearly completely. Season with salt and pepper and set aside.
3. Prepare the Bread: Lightly butter one side of each slice of sourdough bread. Optionally spread Dijon mustard on the unbuttered side of two slices.
4. Assemble the Sandwich: Place bread slices butter-side down in a clean skillet over medium-low heat. Add half of the Swiss cheese on each slice. Layer caramelized onions and sautéed mushrooms over cheese on one slice, then stack the other slice of bread on top, butter side down.
5. Melt and Toast: Cook sandwiches for 3-5 minutes per side until cheese is melted and bread is golden brown and toasted. Cover skillet with a lid if needed to help cheese melt.
6. Serve: Remove sandwiches from skillet, cut in half, and serve immediately for the best gooey, savory melt experience.

Notes

• Use quality sourdough bread and fresh mushrooms for best flavor.
• Be patient with caramelizing onions; low and slow cooking is key.
• Adjust salt and pepper seasoning to your taste during cooking.
• Experiment with other cheeses like Gruyere, provolone, or cheddar for variation.
• Add sauces like garlic aioli, pesto, or balsamic glaze for an extra flavor layer.

Keywords: Swiss Mushroom Melt, caramelized onions, sautéed mushrooms, Swiss cheese sandwich, sourdough sandwich, vegetarian sandwich, comfort food, easy lunch, melted cheese sandwich