These Swiss mushroom burgers swap the beef patty for a thick, garlic butter roasted mushroom cap topped with melted cheese, sweet onions, and a creamy pink sauce.
Roasting turns the mushrooms juicy and deeply savory, almost steak like in texture, while the Swiss cheese melts into a nutty blanket over the top. Piled into toasted buns with lettuce and tomato, they are satisfying enough for a full dinner, even for people who usually reach for meat.
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Why This Swiss Mushroom Burgers Recipe Works
Roasting concentrates the flavor. Brushing the caps with garlic butter and cooking them gills side up lets them collect their own juices, then flipping halfway through browns the surface and leaves a meaty, tender bite.
Slow cooked onions bring sweetness. Cooking the rings in olive oil until soft adds a jammy, savory layer that balances the sharp cheese and the tangy sauce.
The pink sauce ties everything together. Mayonnaise, ketchup, and a little Sriracha make a creamy, tangy, mildly spicy spread that you can tune to your own heat level in seconds.
Ingredients for Swiss Mushroom Burgers
- 4 large portobello mushroom caps, about 20 percent wider than your buns, for the mushrooms
- 2 tbsp unsalted butter, for the mushrooms
- 2 cloves garlic, finely minced, for the mushrooms
- 1/4 tsp kosher salt, for the mushrooms
- 1/2 tsp black pepper, for the mushrooms
- 1/2 tbsp olive oil, for the mushrooms
- 4 slices Swiss cheese, or another sliced cheese
- 3 medium yellow onions, cut into 1/3 inch rings, for the onions
- 1 tbsp olive oil, for the onions
- 1/8 tsp kosher salt, for the onions
- 1/4 tsp black pepper, for the onions
- 2/3 cup mayonnaise, or sour cream with a pinch of salt, for the pink sauce
- 2 tbsp ketchup, for the pink sauce
- 1 to 3 tsp Sriracha, for the pink sauce, to taste
- 4 brioche buns or rolls, for serving
- 8 to 12 lettuce leaves, for serving
- 2 medium tomatoes, sliced, for serving
- Fries or baked potato wedges, to serve alongside
Mushroom caps. Look for wide, flat caps with a smooth top. Remove the stems and scrape out the dark gills if you want a cleaner color and a slightly milder flavor.
Garlic butter. Melted butter with garlic and pepper seasons the caps and helps them brown. Brush the smooth side first, then the rims and gills.
Swiss cheese. Its nutty flavor and smooth melt suit mushrooms well. Any sliced cheese you like melts the same way.
Onions. Slice them into even rings so they soften at the same pace. Cook them gently until they are tender and lightly golden.
Pink sauce. Mix it while the mushrooms roast. It thickens slightly as it sits, and the Sriracha amount sets the heat.
How to Make Swiss Mushroom Burgers
1. Heat the oven Heat the oven to 450 degrees F and line a large tray with parchment paper.
2. Make the garlic butter Place the butter, garlic, salt, and pepper in a heatproof jug. Microwave until the butter melts, then stir.
3. Season the caps Brush the smooth tops of the mushrooms with garlic butter and set them gills side up on the tray. Brush the rest of the butter over the rims and gills, then drizzle with the olive oil.
4. Roast the mushrooms Roast for 25 minutes, flip the caps, brush them with the juices on the tray, and roast 10 minutes more, until tender and browned.
5. Cook the onions While the mushrooms roast, cook the onion rings in a skillet with the olive oil, salt, and pepper over medium heat, stirring often, until soft and golden.
6. Mix the sauce Stir the mayonnaise, ketchup, and Sriracha together in a small bowl.
7. Melt the cheese and build Top each mushroom with a slice of cheese and return it to the oven for 3 minutes, until melted. Split the buns and toast them lightly alongside, then build with lettuce, tomato, a mushroom, onions, and sauce.
How to Serve Swiss Mushroom Burgers
Serve the burgers warm, with a pile of fries on the side and a napkin close by. The natural partner is a basket of crispy homemade fries, while macaroni salad with sour cream makes a cool contrast on a picnic plate. For another burger night idea, compare them with juicy cheeseburgers, and refresh the table with a pitcher of blueberry mojito punch.
How to Store and Reheat Swiss Mushroom Burgers
Store the components separately for the ideal texture. Keep the roasted mushrooms and onions in an airtight container in the refrigerator for up to 3 days, and keep the sauce covered for the same time. Do not store fully assembled burgers, since the buns turn soggy. To reheat, warm the mushrooms and onions in a hot oven at 350 degrees F or a skillet until steaming hot at 165 degrees F, then rebuild the burgers with fresh buns and lettuce.
Tips and Variations for Swiss Mushroom Burgers
Pick wide caps. Caps that are wider than the buns shrink as they roast and end up the right size.
Pat the caps dry. Wipe, do not soak, mushrooms. Water prevents browning.
Use the pan juices. Brush the juices that gather in the caps onto the tops when you flip them. That is pure flavor.
Toast the buns. A quick toast keeps the buns from soaking up the juices and falling apart.
Swap the cheese. Provolone, Gruyere, or pepper jack all melt well on the mushrooms.
Change the sauce heat. Start with 1 teaspoon of Sriracha and taste before adding more.
Add a smoky note. A pinch of smoked paprika in the garlic butter adds a smoky flavor without a grill.
Try another tray idea. Cook mushrooms until tender and hot all the way through, and for another easy tray roasting idea see the Idaho Health Matters sheet pan recipe.
Frequently Asked Questions About Swiss Mushroom Burgers
What mushrooms work well for swiss mushroom burgers?
Large portobello or flat cap mushrooms are ideal because they are wide, thick, and meaty. Choose caps about 20 percent wider than the buns.
Can I make swiss mushroom burgers ahead of time?
Roast the mushrooms, cook the onions, and mix the sauce ahead, then store each separately. Reheat the mushrooms, melt the cheese, and assemble just before serving.
How do I keep swiss mushroom burgers from getting soggy?
Roast them until the juices cook down, pat off any extra liquid, toast the buns, and assemble right before eating.
Are these burgers meatless?
Yes, they contain no meat. Check your cheese, since some are made with animal rennet, and choose a bun without animal products if that matters to you.
Can I use sour cream in place of mayonnaise?
Yes. Mix sour cream with a pinch of salt, then add the ketchup and Sriracha as written. The sauce will be a little tangier and lighter.
Swiss Mushroom Burgers
Equipment
- Rimmed baking tray
- Parchment paper
- Skillet
- Heatproof jug
Ingredients
Main Ingredients
- 4 large portobello mushroom caps about 20 percent wider than the buns
- 2 tbsp unsalted butter for the mushrooms
- 2 cloves garlic finely minced, for the mushrooms
- ¼ tsp kosher salt for the mushrooms
- ½ tsp black pepper for the mushrooms
- ½ tbsp olive oil for the mushrooms
- 4 slices Swiss cheese or another sliced cheese
- 3 medium yellow onions cut into 1/3 inch rings, for the onions
- 1 tbsp olive oil for the onions
- ⅛ tsp kosher salt for the onions
- ¼ tsp black pepper for the onions
- ⅔ cup mayonnaise or sour cream with a pinch of salt, for the sauce
- 2 tbsp ketchup for the sauce
- 2 tsp Sriracha for the sauce, adjust to taste
- 4 brioche buns or rolls, for serving
- 8 lettuce leaves for serving
- 2 medium tomatoes sliced, for serving
Instructions
Cooking
- Heat. Heat the oven to 450 degrees F. Make the garlic butter. Melt the butter with the garlic, salt, and pepper in the microwave, then stir.
- Brush. Coat the smooth side of each cap with the butter, set the caps gills side up on a tray, brush the rims and gills, and drizzle with oil.
- Roast. Roast 25 minutes, flip, baste with the tray juices, and roast 10 minutes more, until tender and browned.
- Cook the onions. Soften the onion rings in a skillet with the oil, salt, and pepper over medium heat until golden.
- Mix the sauce. Stir the mayonnaise, ketchup, and Sriracha together.
- Melt and build. Top each cap with Swiss cheese and return to the oven for 3 minutes. Toast the buns, then layer lettuce, tomato, a mushroom, onions, and sauce.
