Mushroom Swiss Burgers with Caramelized Onions
Juicy Mushroom Swiss Burgers with Caramelized Onions make the ultimate comfort food dinner. This easy burger recipe delivers rich, savory flavor in every bite and is perfect for grilling season, but it’s just as delicious made on the stovetop, a griddle, or a grill pan.
Best Mushroom Swiss Burger
It’s no secret that Mike and I are big mushroom lovers. I find ways to work this umami-rich veggie into so many SueBee recipes – and I’m just as happy sautéing a simple batch to serve alongside any protein.
There are so many great burger spots here in Texas, and we often find ourselves ordering mushroom Swiss burgers when we go out. But with our warm weather, we’re grilling at home more than ever, especially since my husband has basically turned our backyard into a tropical oasis… so really, why leave?
You may have noticed that we’re not stopping at mushrooms and Swiss cheese – we’re piling on a generous scoop of caramelized onions, too. Let me tell you, this just might be the burger recipe of the year!
Why This Recipe Works:
- Big flavor layers: Earthy mushrooms, melty Swiss cheese, and sweet caramelized onions create a rich, savory combination that feels indulgent without extra effort.
- Juicy, satisfying texture: The mushrooms add moisture and umami, helping the burger stay juicy while enhancing the beefy flavor.
- Simple ingredients: Basic pantry staples come together to create a gourmet-style burger that feels restaurant-worthy.
- Flexible cooking methods: Works great on the grill, stovetop, or griddle, making it an easy go-to for weeknights or weekend cookouts.
What You’ll Need:
- ground beef – I recommend using 80-85% lean ground beef.
- seasonings – a combo of onion powder, garlic powder, kosher salt, and freshly ground black pepper
- olive oil plus butter
- mushrooms – We prefer using Bella mushrooms for this recipe.
- onions – one yellow onion, sliced
- baby Swiss cheese
- hamburger buns – We rotate between our Pretzel Sandwich Buns Recipe, Soft Burger Buns, or Homemade Hoagie Rolls (but in bun form).
How to make Mushroom Swiss Burgers:
Step 1
Caramelize onions. Add butter to a medium cast iron skillet over medium heat. When melted, add sliced onion, salt, and pepper – and cook, stirring frequently to avoid burning. You may need to add splashes of water to moisten the onions as they cook. Continue cooking until onions get nice and golden brown, about 30 minutes.
NOTE: If you are feeding a crowd and making extra onions, it may take longer than 30 minutes to fully caramelize.
Step 2
Brown mushrooms. Add olive oil to skillet heated over medium-high heat. Add sliced mushrooms to skillet and cook. It will take approximately 10 minutes to brown them properly (longer if making more quantity of mushrooms). Then add salt and pepper to taste.
Step 3
Prep burgers. Press ground beef into four equal-sized patties, making a slight indention in the centers. Add seasonings to both sides of patties.
Step 4
Prepare grill. Light an outdoor grill to medium-high heat. Add wood chips for extra smoky flavor, if desired.
Step 5
Grill burgers. Gently set the prepared beef burgers on the hot grill grates. Grill burgers until they reach your desired temperature, flipping burgers about halfway through. Add Swiss cheese at the very end and let melt. We like our burgers a bit pink in the insides but proceed with caution.
Burger Doneness Temps:
The U.S. Food and Drug Administration recommends cooking ground beef (including burgers) to an internal temperature of 160°F (71°C) to ensure it’s safe to eat. We normally cook ours to medium, FYI.
- Rare: 120 – 125
- Medium Rare: 130 – 135
- Medium Well: 150 – 155
- Well Done: 160 – 165
Step 6
Assemble burgers. Place the grilled burgers on buns. Top with caramelized onions and browned mushrooms. Beware – these are messy!
What to serve with Mushroom Swiss Burgers:
I’ve got lots of sides for you to choose from, but these are some of my favorites.
Tips for making the perfect burger:
- Use a higher fat ground meat. I recommend no leaner than 85%.
- Don’t overwork the meat. This will ensure the meat isn’t tough.
- If making regular patties, press your thumb into the center of the raw patty to form an indentation. We don’t want the center to plump up.
- Season liberally. Season the patties right before you cook them. Salt applied too far in advance will toughen the meat.
- Use high heat. Grill the burgers at 400 degrees or higher.
- Try to avoid flipping the patties too often. Let them cook on one side for several minutes before flipping to the other side.
- Don’t overcook. My family prefers a bit of pink but proceed at your own risk.
Recipe FAQs:
Baby bella (cremini) mushrooms are ideal because they have a deeper, meatier flavor, but white button mushrooms work great too.
Cook them low and slow over medium-low heat with a little butter or oil, stirring often. If they start to stick, add a splash of water or broth to deglaze the pan.
Classic deli-style Swiss slices melt smoothly and evenly, but Gruyère is a great upgrade if you want a nuttier flavor.
Yes. Sauté them up to 2–3 days ahead and store in the fridge. Reheat in a skillet or microwave before assembling your burgers.
Don’t overwork the meat, make a slight indentation in the center of each patty, and avoid pressing the patties while cooking.
Absolutely. A cast-iron skillet or stovetop grill pan works perfectly for juicy burgers with a nice sear.
Other Delicious Burger Recipes:
We have other delicious burgers for you to choose from next!
Kitchen Tools Used: (affiliate links)
xoxo ~Sue
Mushroom Swiss Burgers with Caramelized Onions
Ingredients
- 1 ½ pounds 85% ground beef
- kosher salt and freshly ground black pepper – to taste
- 1/2 teaspoon EACH onion powder, garlic powder
- 2 Tablespoons unsalted butter
- 1 large yellow onion – sliced
- 1-2 Tablespoons olive oil
- 8 oz. sliced Bella mushrooms
- 4 slices baby swiss cheese
- hamburger buns – to serve
Instructions
- Caramelize onions. Add butter to a medium cast iron skillet over medium heat. When melted, add sliced onion, salt, and pepper – and cook, stirring frequently to avoid burning. You may need to add splashes of water to moisten the onions as they cook. Continue cooking until onions get nice and golden brown, about 30 minutes.NOTE: If you are feeding a crowd and making extra onions, it may take longer than 30 minutes to fully caramelize.2 Tablespoons unsalted butter, 1 large yellow onion
- Brown mushrooms. Add olive oil to skillet heated over medium-high heat. Add sliced mushrooms to skillet and cook. It will take approximately 10 minutes to brown them properly (longer if making more quantity of mushrooms). Then add salt and pepper to taste.1-2 Tablespoons olive oil, 8 oz. sliced Bella mushrooms
- Prep burgers. Press ground beef into four equal-sized patties, making a slight indention in the centers. Add seasonings to both sides of patties.1 ½ pounds 85% ground beef, kosher salt and freshly ground black pepper , 1/2 teaspoon EACH onion powder, garlic powder
- Prepare grill. Light an outdoor grill to medium-high heat. Add wood chips for extra smoky flavor, if desired.
- Grill burgers. Gently set the prepared beef burgers on the hot grill grates. Grill burgers until they reach your desired temperature, flipping burgers about halfway through. Add Swiss cheese at the very end and let melt. We like our burgers a bit pink in the insides but proceed with caution.4 slices baby swiss cheese
- Assemble burgers. Place the grilled burgers on buns. Top with caramelized onions and browned mushrooms. Beware – these are messy but worth it!hamburger buns
Notes
- Pictured are our homemade pretzel buns. So good!
- You can make these burgers indoors on a grill pan or cast iron skillet.
Tips for making the perfect burger:
- Use a higher fat ground meat. I recommend no leaner than 85%.
- Don’t overwork the meat. This will ensure the meat isn’t tough.
- If making regular patties, press your thumb into the center of the raw patty to form an indentation. We don’t want the center to plump up.
- Season liberally. Season the patties right before you cook them. Salt applied too far in advance will toughen the meat.
- Use high heat. Grill the burgers at 400 degrees or higher.
- Try to avoid flipping the patties too often. Let them cook on one side for several minutes before flipping to the other side.
- Don’t overcook. My family prefers a bit of pink but proceed at your own risk.