Upside-Down Mushroom Burger

The ultimate mushroom lover's mushroom burger, this recipe packs the hamburger patty right into the cap of a jumbo portobello for intense mushroom flavor in every bite.

Serves: 4Prep: 8 minutesCook: 12 minutesTotal: 20 minutesDifficulty: Medium

Serves: 4


  • 4 large portobello mushrooms (approximately 4" diameter)
  • 1 tablespoon soy sauce
  • 1 teaspoon Worcestershire sauce
  • 2 tablespoons oil or melted butter
  • 4 ounces Monterey Jack cheese, shredded
  • 1 1⁄4 pounds (20 oz.) ground beef, 85% lean
  • 1⁄2 teaspoon sea salt, or to taste
  • 6-inch freshly ground black pepper, or to taste
  • 4 hamburger buns or split kaiser rolls


  • Heat your grill to a medium-high cooking temperature, approximately 400° F to 425° F.
  • Remove the stems from the mushrooms by bending them until they snap free. Reserve those for use in another recipe (they'll keep a few days in the fridge). Scrape the dark gills from the mushrooms with a teaspoon, leaving the cap as a hollow shell.
  • Brush the insides of the mushroom caps with the soy sauce and Worcestershire sauce, then brush the outsides with the oil or melted butter. Divide the shredded cheese between the mushroom caps, then set them aside.
  • Break up the ground beef with your fingers to loosen it, then season it lightly with salt and pepper. Shape it into four loose patties and press each patty firmly into each of the mushroom caps.
  • Place the mushrooms on the grill, beef side down. Grill for 4-5 minutes on the first side, or until the beef is browned and the cheese begins to ooze down the sides. Flip to the mushroom side and grill for another 7-8 minutes until the mushroom is tender. The burgers should show a food-safe internal temperature of 160° F when tested with an instant-read thermometer.
  • Transfer each burger to a bun and serve immediately with your choice of toppings and condiments. Any leftovers should be refrigerated as soon as possible, no more than 2 hours after cooking, and eaten within four days.
  • Tips: Bacon and grilled or caramelized onions are especially good with these burgers. If any of your friends or family prefer low-carb meals, you can use a second mushroom cap to fully enclose the burger. It won't need a bun, and will be ready to eat as soon as it's cooled enough to handle. Slide your thermometer horizontally into the middle of the patty to test the burger's temperature. You won't get an accurate reading if you try to test the temperature by inserting it from above.