Learn how to make the BEST sweet onion and mushroom swiss burgers! The burger patty is juicy and perfectly seasoned, but it's the mushrooms and onions really take it over the top! Top it off with swiss cheese, and you will see why it's so addicting!

Prep Time

    •    Prep time: 10 minutes
    •    Cook time: 55 minutes
    •    Yield: Serves 4

Ingredients

For the Caramelized Onions:

    •    1 tsp sugar
    •    1 ½ tbsp oil
    •    ¾ tsp kosher salt
    •    1 jumbo onion, thinly sliced

For the Swiss Mushroom Burgers:

    •    4 burger buns
    •    1 tbsp olive oil
    •    1 tbsp garlic powder
    •    1 ¼ pounds ground beef
    •    arugula, for topping (Optional)
    •    8 ounces sliced baby bella mushrooms
    •    Swiss cheese, for topping (or any other cheese you like)
    •    1 tsp EACH: kosher salt, black pepper and onion powder

Method

1. Onions: heat the oil in a large skillet over high heat. Add the onions and allow them to sizzle for about 5 minutes stir as required so nothing sticks or burns. Season the onions with the sugar and salt. Lower the heat to medium-low, and all the onions to cook for 25-45 minutes stirring every 7-10 minutes (about every 5 minutes near the end) so nothing sticks. I like the onions around the 45-minute mark, but how far you take the onions is entirely up to you. MAKE AHEAD: at this point, you can remove the onions to a container, allow them to cool to room temperature and refrigerate them for up to 3 days!
   
   
2. Patties: In a small bowl, combine the garlic powder, salt, black pepper, and onion powder; set aside. Divide the ground beef into 4 equal portions. Form into a round ball shape. Grab 2 pieces of plastic wrap and place one sheet of plastic wrap on a flat surface and place the meat ball on top, followed by the second sheet of plastic wrap. Using a concave lid, or even a large flat spatula, press the ball down into a flat patty. Set aside 1 teaspoon of this seasoning and use the remaining to season the patties (on both sides) evenly.
   
   
3. Mushrooms: Prepare the grill (if you’re grilling outdoors.) While the grill is heating, heat a large sauté or cast iron pan over medium-high heat. Add the oil and the mushrooms to the skillet and allow them to cook for 2-3 minutes. When the mushrooms start browning, season them with the reserved teaspoon of seasoning and toss. Remove from heat into a bowl or a plate.
   
   
4. Cook + Assemble: Cook the patties on the same skillet (or outdoors) for roughly 3-5 minutes per side (indoors) it may take a little longer on an outdoor grill or until it reaches your desired doneness. When the burgers are almost done, lay the Swiss cheese over them and allow it to melt. Remove to a plate when done. You can also toast the buns with just a brush of oil if you’d like. When ready to assemble, place the burger patty on the bun and top with the sautéed mushrooms, onions, and a handful of arugula if you want a little freshness!

This great family recipe is thanks to Little-Spice-Jar Recipes at https://littlespicejar.com/sweet-onion-mushroom-swiss-burgers/