As National Mushroom Month progresses, we continue to find delicious ways to enjoy the edible fungi. We’ve made Mushroom Grilled Cheese before, (Mushroom Grilled Cheese Sandwich, Grilled Mushroom & Fontina Sandwich) but this one is different. It is more of a patty melt with large, roasted portobello caps replacing the traditional beef patty. Caramelized onions enhance the sandwich and the eating pleasure.

Roasted in the oven in a marinade of oil, balsamic vinegar, soy, and garlic, the portobellos are immensely flavorful and meaty. Using the larger caps adds more of the umami flavor and mouth feel that beef patties typically provide. The onions are transformed from sharp tasting to a sweet and delectable addition to the sandwich when they are caramelized. Melty Swiss cheese and butter-griddled rye bread round out the sensational taste of this melt. Let’s get to it!

Mushroom & Caramelized Onion Melts

Mushroom & Caramelized Onion Melts (adapted from cooking.nytimes.com) Total Time Required: 1 hour, Yield: 4 servings

Ingredients:

• 6 tablespoons unsalted butter, divided
• 2 large onions, peeled and thinly sliced
• kosher salt and freshly ground black pepper to taste
• 8 slices rye bread
• 8 slices (1/2 pound) Swiss cheese
• 1 tablespoon olive oil
• 2 tablespoons soy sauce
• 2 tablespoons balsamic vinegar
• 1 minced garlic clove
• 8 portobello caps, wiped of debris with gills removed

Preparation:

Prep the mushrooms and onions.

Wash & remove the gills from the mushrooms.

Thinly slice the onions.

Preheat the oven to 400º F. In a small bowl, mix together the olive oil, soy sauce, balsamic vinegar, and minced garlic.

Mix up the marinade for the mushrooms.

Pour the mixture in a baking dish large enough to hold the caps in a single layer and add the prepped portobellos. Cover the dish with foil, and roast the mushrooms in the oven for 30 to 45 minutes, turning once.

The portobellos are ready for roasting!

Caramelize the onions. Melt 2 tablespoons of the butter in a large skillet set over high heat. When the butter foams, add the onions to the pan and sprinkle them with salt. Wait 1 minute, then begin to stir the onions frequently over high heat for 5 minutes or so, until the onions have released some liquid and started to become translucent.

Caramelize the onions.

Reduce the heat to medium, and cook, stirring often, until the onions are fully melted and dark golden brown, approximately 30 to 40 minutes. Remove the onions from the pan and set them aside.

When the mushrooms and onions are ready, return the large skillet to the stove over medium heat. Using the rest of the butter, spread 1/2 tablespoon on each of the 8 slices of rye bread.

Butter one side of each of the bread slices.

Place 4 of the bread slices in the pan, buttered side down, and top each piece with a slice of cheese, two portobello caps, some of the caramelized onions, then another slice of cheese.

Start with the mushroom caps and onions . . .

. . . then add another slice of cheese.

Top each melt with a remaining slice of bread, buttered side up. Press down on the sandwiches, and after 1-2 minutes, carefully turn over each one to brown the other side.

Flip the sandwiches over to brown the second side.

Cook the melts until the cheese is fully melted and the bread is golden brown and crisp on both sides. Slice in half and serve.

So flavorful and delicious!!

A perfect meal for Autumn!  ~Linda

Mushroom & Caramelized Onion Melts (adapted from cooking.nytimes.com) Total Time Required: 1 hour, Yield: serves 4

Ingredients:

• 6 tablespoons unsalted butter, divided
• 2 large onions, peeled and thinly sliced
• kosher salt and freshly ground black pepper to taste
• 8 slices rye bread
• 8 slices (1/2 pound) Swiss cheese
• 1 tablespoon olive oil
• 2 tablespoons soy sauce
• 2 tablespoons balsamic vinegar
• 1 minced garlic clove
• 8 portobello caps, wiped of debris with gills removed

Preparation:

Prep the mushrooms and onions.

Preheat the oven to 400º F. In a small bowl, mix together the olive oil, soy sauce, balsamic vinegar, and minced garlic. Pour the mixture in a baking dish large enough to hold the caps in a single layer and add the prepped portobellos. Cover the dish with foil, and roast the mushrooms in the oven for 30 to 45 minutes, turning once.

Caramelize the onions. Melt 2 tablespoons of the butter in a large skillet set over high heat. When the butter foams, add the onions to the pan and sprinkle them with salt. Wait 1 minute, then begin to stir the onions frequently over high heat for 5 minutes or so, until the onions have released some liquid and started to become translucent. Reduce the heat to medium, and cook, stirring often, until the onions are fully melted and dark golden brown, approximately 30 to 40 minutes. Remove the onions from the pan and set them aside.

When the mushrooms and onions are ready, return the large skillet to the stove over medium heat. Using the rest of the butter, spread 1/2 tablespoon on each of the 8 slices of rye bread. Place 4 of the slices in the pan, buttered side down, and top each piece with a slice of cheese, two portobello caps, some of the caramelized onions, then another slice of cheese. Top each melt with a remaining slice of bread, buttered side up. Press down on the sandwiches, and after 1-2 minutes, carefully turn over each one to brown the other side. Cook the melts until the cheese is fully melted and the bread is golden brown and crisp on both sides. Slice in half and serve.