Vegetarian Grilling: Barbecued Portobello “Cheeseburgers” Recipe
Prep Time
Cooking Time
Total Time
Yield: 6
  • 1 bottle Weber® Original BBQ Sauce, divided
  • ¼-cup apple cider vinegar
  • ½ -cup olive oil
  • 6 large portabella mushrooms (same size as rolls)
  • 1 large Vidalia onion, cut into 6 thick slices
  • ½-pound white cheddar cheese, sliced thin
  • ½-pound Parmesan-Reggiano cheese, sliced thinly (a vegetable peeler works well)
  • 6 onion or Kaiser rolls
  • Head of garlic, roasted
  • ½-cup quality mayonnaise
  • 2 Tablespoons Weber® Original BBQ Sauce
  • Kosher salt and freshly ground pepper, to taste
  • Sour or dill pickle slices, optional
  1. MARINADE: Mix half of the Weber® Original BBQ Sauce with vinegar and olive oil. Set aside. In a large bowl, add sliced onions and cleaned mushrooms (stems removed). Add the marinated to the mushrooms and onions and marinate for 10 to 30 minutes.
  2. GRILLING: Remove the vegetables from the marinade and place them on the hot grill. Grill 8-10 minutes (grill the mushrooms gill-side up). Turn over the vegetables and brush with additional marinade. The mushrooms should be tender and the onions should still be crisp.
  3. ASSEMBLY: While the vegetables are grilling, mix the roasted garlic and mayonnaise with 2 tablespoons of the Weber® Original BBQ. Mix until smooth.
  4. Split Kaiser or onion rolls in half. Spreading both sides of the roll with garlic-BBQ sauce mayonnaise mixture.
  5. Layer mushroom, onions and both cheeses. (if you prefer your cheese melted, add it to the mushrooms on the grill just before removing)
  6. Season with salt and pepper if desired. Place top of roll on each sandwich, top with pickles and cut in half before serving.
Recipe by Baby to Boomer Lifestyle at