Swiss Mushroom Melt Sandwich Recipe

Introduction

The Swiss Mushroom Melt Sandwich is a comforting and flavorful treat featuring sweet caramelized onions, savory sautéed mushrooms, and melted Swiss cheese on toasted sourdough. This sandwich combines rich textures and deep, savory flavors perfect for a satisfying lunch or dinner.

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, but recommended)
• 1 tablespoon fresh thyme leaves
• Salt and freshly ground black pepper to taste
• 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. Step 1: Peel and thinly slice the yellow onions.
2. Step 2: In a large skillet, heat 2 tablespoons olive oil and 1 tablespoon butter over medium-low heat.
3. Step 3: Add the sliced onions and stir to coat them evenly in the fat.
4. Step 4: Cook the onions over very low heat, stirring occasionally, for about 30-45 minutes until they are deep golden brown and very soft. Reduce heat if they start to brown too quickly.
5. Step 5: Stir in the brown sugar and balsamic vinegar. Cook for another 2-3 minutes, stirring constantly, until the sugar dissolves and the vinegar is absorbed.
6. Step 6: Season the caramelized onions with salt and freshly ground black pepper to taste. Remove from the skillet and set aside.
7. Step 7: Clean and slice the cremini mushrooms.
8. Step 8: In the same skillet, heat 2 tablespoons olive oil over medium-high heat.
9. Step 9: Add the sliced mushrooms and cook, stirring occasionally, until browned and softened, about 8-10 minutes. Cook in batches if needed to avoid overcrowding.
10. Step 10: Add the minced garlic and fresh thyme leaves. Cook for another minute, stirring constantly, until fragrant.
11. Step 11: Pour in the white wine and scrape up any browned bits from the pan. Let the wine reduce for 1-2 minutes until nearly evaporated.
12. Step 12: Season the mushrooms with salt and freshly ground black pepper to taste. Remove from the skillet and set aside.
13. Step 13: Lightly butter one side of each slice of sourdough bread.
14. Step 14: Spread a thin layer of Dijon mustard on the unbuttered side of two slices of bread.
15. Step 15: Place the bread slices buttered side down in a clean skillet over medium-low heat. On each slice, layer half of the Swiss cheese.
16. Step 16: On one slice, pile half of the caramelized onions and half of the sautéed mushrooms on top of the cheese. Repeat on the other slice.
17. Step 17: Top each with the remaining Swiss cheese, then place the other bread slices on top, buttered side up.
18. Step 18: Cook the sandwiches for 3-5 minutes per side until the cheese is melted and gooey, and the bread is golden brown and toasted. Cover the skillet with a lid to help the cheese melt faster.

Tips & Variations

• Use a mix of mushroom varieties like shiitake or portobello for deeper flavor.
• Swap Swiss cheese with Gruyère or fontina for a slightly different melt and taste.
• Add a handful of fresh spinach or arugula inside the sandwich for a fresh, peppery bite.
• If you prefer a vegan version, use plant-based butter and cheese alternatives.

Storage

Store leftover sandwiches wrapped tightly in foil or plastic wrap in the refrigerator for up to 2 days. To reheat, warm gently in a skillet over low heat or in a toaster oven until heated through and the cheese is melted again. Avoid microwaving if possible, 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 caramelized onions and sautéed mushrooms can be prepared up to 2 days in advance and stored in an airtight container in the refrigerator. Reheat gently before assembling the sandwiches.

What type of bread works best for this sandwich?

Sourdough is ideal due to its sturdy texture and tangy flavor, but you can also use other firm breads like rye, multigrain, or a rustic Italian loaf.

Swiss Mushroom Melt Sandwich Recipe

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The Swiss Mushroom Melt Sandwich is a savory and comforting vegetarian sandwich featuring deeply caramelized onions, sautéed cremini mushrooms infused with garlic and thyme, and melted Swiss cheese, all layered on toasted sourdough bread with a touch of Dijon mustard. Perfect for a hearty lunch or light dinner, this sandwich blends rich umami flavors with creamy melted cheese and a crispy golden crust.

• Author: Marco
• 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. Prepare the onions: Peel and thinly slice the yellow onions to ensure they caramelize evenly.
2. Cook the onions: In a large skillet, heat olive oil and butter over medium-low heat. Add the sliced onions and stir to coat.
3. Caramelize the onions: Cook the onions over very low heat, stirring occasionally, for about 30-45 minutes, until they become deeply golden brown and very soft. Reduce heat if browning too fast.
4. Add sugar and vinegar: Stir in brown sugar and balsamic vinegar, cooking for another 2-3 minutes while stirring constantly until sugar dissolves and vinegar is absorbed.
5. Season onions: Add salt and freshly ground black pepper to taste, then remove the caramelized onions from the skillet and set aside.
6. Prepare the mushrooms: Clean and slice the cremini mushrooms for even cooking.
7. Sauté mushrooms: In the same skillet, heat olive oil over medium-high heat. Add mushrooms, cooking and stirring occasionally for 8-10 minutes until browned and softened. Cook in batches if needed to avoid overcrowding.
8. Add garlic and thyme: Stir in minced garlic and fresh thyme leaves, cooking for another minute until fragrant.
9. Deglaze pan: Pour white wine into the skillet, scraping up browned bits from the bottom. Let the wine reduce for 1-2 minutes until nearly evaporated.
10. Season mushrooms: Add salt and freshly ground black pepper to taste. Remove mushrooms from skillet and set aside.
11. Prepare bread: Lightly butter one side of each slice of sourdough bread.
12. Add mustard: Spread a thin layer of Dijon mustard on the unbuttered side of two bread slices.
13. Assemble sandwiches: Place bread with buttered side down on a clean skillet over medium-low heat. On these slices, layer half of the Swiss cheese first.
14. Add fillings: On top of the cheese on one slice, pile half of the caramelized onions and half of the sautéed mushrooms. Repeat on the other slice with remaining fillings.
15. Cook sandwiches: Top each with the remaining Swiss cheese slice, then place the other bread slice buttered side up on top to close the sandwich. Cook for 3-5 minutes per side, until cheese melts and bread is golden and toasted. Cover the skillet with a lid to speed melting.

Notes

• Cooking the onions slowly and patiently is key to developing their deep caramelized flavor.
• White wine enhances the flavor of the mushrooms but can be omitted for a non-alcoholic version; substitute with vegetable broth if desired.
• Use good quality Swiss cheese for best melt and flavor.
• Adjust seasoning at the end to taste, as salt enhances the sweetness of the caramelized onions and earthiness of the mushrooms.
• For a vegan version, substitute butter and cheese with plant-based alternatives and skip the Dijon mustard if non-vegan.

Keywords: Swiss Mushroom Melt, caramelized onion sandwich, sautéed mushrooms, vegetarian sandwich, melted Swiss cheese, sourdough sandwich