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Caramelized Onion, Mushroom, and Swiss Melt

4.25 from 4 votes
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An easy sandwich to put together but the flavors will make it seem as if you spent all day making it! The caramelized onions bring a sweet and unique flavor that helps make this sandwich irresistible! Get this caramelized onion, mushroom, and swiss cheese melt on your table!

An easy sandwich to put together but the flavors will make it seem as if you spent all day making it! The caramelized onions bring a sweet and unique flavor that helps make this sandwich irresistible! Get this caramelized onion, mushroom, and swiss cheese melt on your table!

We’re on day #4 of blizzard 2016 dig out. There are still so many residential roads that still haven’t been touched. The schools are still closed around here and the federal government is still telling employees to stay home and telework. This is so crazy! There is SO much snow that they really just have nowhere to put it even if they’re plowing. Like, our main roads and interstates have pretty much turned into 1 or 2 lane roads. And there’s like no warning. You’ll be driving and all of a sudden it’s like ‘woah my lane is gone.’ It’s pretty treacherous and I can’t imagine what rush hour is going to be like once everyone starts going back to work. Niiiightmare!

In other news, Winston gets his cast off today! He is going to be so happy but he won’t realize that the happiness will be short-lived. He is going to be restricted on so many things that he will think is normal. No jumping, no running, no rough-housing/playing with other dogs, no nothing! We’re going to have to tell ‘no!’ on basically everything he tries to do. This is only the beginning of the long road to recovery. It’s going to be really hard and going to test our (and his) patience so much. But like Jason said, this short-term nuisance will give him a long-term better quality of life. I just wish he understood that :) happy thoughts for the next 16 weeks would be appreciated!

An easy sandwich to put together but the flavors will make it seem as if you spent all day making it! The caramelized onions bring a sweet and unique flavor that helps make this sandwich irresistible! Get this caramelized onion, mushroom, and swiss cheese melt on your table!

During this blizzard, all I have been craving is pure comfort food. The stick to your ribs kind and the not-so-good-for-you kind. It’s the cold weather, I’m tellin’ ya!

So this caramelized onion, mushroom, and Swiss melt was actually a recipe that was supposed to be in the cookbook! However, I took it out in the end because it didn’t seem very ‘dinner’ and filling for a dinner entree. However, this would be a great lunch option or a delicious dinner with a soup on the side! Omg, yes!

An easy sandwich to put together but the flavors will make it seem as if you spent all day making it! The caramelized onions bring a sweet and unique flavor that helps make this sandwich irresistible! Get this caramelized onion, mushroom, and swiss cheese melt on your table!

An easy sandwich to put together but the flavors will make it seem as if you spent all day making it! The caramelized onions bring a sweet and unique flavor that helps make this sandwich irresistible!

Caramelized Onion, Mushroom, and Swiss Melt

An easy sandwich to put together but the flavors will make it seem as if you spent all day making it! 
4.25 from 4 votes
Prep Time: 10 minutes
Cook Time: 35 minutes
Total Time: 45 minutes
Servings: 2
Author: Julie Chiou
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Ingredients 

  • 3 teaspoons vegetable oil, divided
  • ½ large onion, sliced into half circles
  • 5 ounces (142 g) baby portabella mushrooms, sliced
  • 1 teaspoon kosher salt, divided
  • ½ cup (54 g) freshly shredded Swiss cheese, divided
  • 4 slices of thick bread, (Italian, French, sourdough, or your favorite)
  • 1 tablespoon (14 g) unsalted butter, room temperature

Instructions 

  • In a skillet over medium-high heat, add 2 tsp. of vegetable oil. When oil is hot, add the onions and 1/2 tsp. of salt and cook until dark brown in color and softened. Halfway through, you’ll want to turn down the heat to medium heat. Caramelizing onions will take about 20-30 minutes. If you notice that your pan is getting slightly dry, adding a tablespoon of water will help the caramelizing along. The water should sizzle and quickly evaporate. You’re not trying to have the water stay in the bottom of the skillet while cooking the onions.
  • When the onions are caramelized, remove from skillet and place in a bowl. Add the remaining 1 tsp. of vegetable oil to the skillet and add the mushrooms and remaining 1/2 tsp. of salt. Cook the mushrooms until softened, about 5 minutes. Remove from skillet; keeping the liquid that has accumulated in the skillet.
  • Preheat broiler in oven.
  • Take the room temperature butter and butter both sides of bread. Place bread on to a baking sheet and place under broiler for about 1 minute each side. Carefully remove bread from baking sheet and on an even surface, begin to assemble your sandwich.
  • Place caramelized onions on one slice of bread, then the mushrooms on top, then 1/4 cup of shredded Swiss cheese. Gently place on baking sheet. Repeat with another slice of bread. Place baking sheet into the oven and broil for 1-2 minutes until cheese is melted and bubbly.
  • Remove from oven and place the remaining two slices of bread on top of each and gently press down.
  • Slice sandwiches in half and serve!

NUTRITION FACTS

Serving: 1 sandwich | Calories: 572 kcal | Carbohydrates: 45 g | Protein: 16 g | Fat: 38 g | Fiber: 3 g | Sugar: 4 g

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The default measuring system for this website is US Customary. Unit conversions are provided for convenience and as a courtesy only. While we strive to provide accurate unit conversions, please be aware that there may be some discrepancies.

Recipe Rating




Rosario

Friday 4th of December 2020

Is the nutrition information for 1/2 of the sandwich or 2 halves?

Rosario

Monday 7th of December 2020

@Julie Chiou, wonderful, thank you!

Julie Chiou

Monday 7th of December 2020

sorry for the confusion. it's for 1 full sandwich.

C. Schneck

Sunday 10th of November 2019

Delicious and easy!

Barbara

Saturday 3rd of August 2019

These were amazing! I will make them again, and will add more mushrooms.

Deborah Johnson

Sunday 30th of September 2018

If you are a fan of carmelized onions and sauteed mushrooms, you will love this sandwich. It is so simple to make but oh so good!

Anni

Monday 30th of July 2018

I just learned how to caramalize oniobs thank u i will try this for lunch today