In a frying pan heat the oil on high. Add carrots and mushrooms. Sauté, stirring until mushrooms brown and liquid evaporates; about 8 minutes. Allow mixture to come to room temperature. Preheat grill or BBQ.
In a bowl mix together the remaining ingredients. Then stir in the mushrooms and carrot.
Form into 4 hamburger patties. Cook for 3-4 minutes each side for medium-rare.
My husband was less enthusiastic about this burger than I, but I'm giving it 5 stars because it's good! I think some garlic aioli would be a great dressing on this, and next time (yes, there will be a next time), I will add a sliced of grilled onion. - 07 May 2013