Ingredients
  • 4 tablespoons olive oil
  • 1 medium onion, chopped
  • 3 portobello mushrooms, finely chopped
  • 2 cloves garlic, minced
  • Salt and black pepper
  • 1 large egg
  • 1/2 cup walnuts, finely chopped
  • 1/2 cup chopped fresh parsley
  • 1/4 cup breadcrumbs
  • 4 slices (4 ounces) Gruyère or Swiss cheese
  • 4 multigrain or gluten-free buns
Preparation

Warm 2 tablespoons of the oil in a large skillet over medium-low heat. Cook the onion, mushrooms, garlic, and salt and pepper to taste until the mushrooms are soft, stirring.

In a large bowl, combine the egg, mushroom mixture, walnuts, parsley and breadcrumbs. Form 4 patties, using about 1/2 cup per patty.


Warm the remaining 2 tablespoons oil in the same skillet over medium-high heat. Cook the patties for 5 minutes on each side, or until browned. Lay a slice of cheese on top of each burger and continue to cook until melted.

Serve the burgers with the buns.