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Swiss Mushroom Melt Sandwich Recipe

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★★★★★

4.6 from 780 reviews

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.

Ingredients

Scale

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

Find it online: https://cookcrisis.com/swiss-mushroom-melt-sandwich-recipe/