Mushroom and onion burger, great for the weekend and low in carbs. Must try!
Finely chop the garlic, pepper and chilli and mix in with beef and egg whites. Form patties and cook to desired level. While the burgers are cooking, melt the butter or heat the oil in a frying pan over medium-high heat.
Add the onion and mushrooms and saute until the onions are translucent. Put burgers onto large romaine leaves and top with mixture.