Just because meat is absent from these burgers doesn't mean that tremendous flavor isn't still present. The Provolone, tomato, and mushroom blend together for a burger that is equal parts healthy and tasty.
Recipe and photo courtesy Susan Randall @ Simple Healthy Kitchen
Preheat oven to 400°F. Line a baking sheet with foil and set aside. Clean mushrooms, and remove stems and gills.
In a small bowl combine olive oil, balsamic vinegar, honey, garlic, and salt and pepper. Pour the balsamic mixture into a zip-lock bag with mushrooms. Shake gently to coat the mushrooms. Let marinate for at least 15 mins.
Cut tomatoes in half and place in a pyrex or other oven-safe dish. Salt and pepper to taste. Set aside.
When mushrooms have finished marinating, remove from zip-lock (reserving marinade) and place open side-up on foil-lined baking sheet. Pour remaining marinade over dish of tomatoes.
Bake both for 20 mins. (turning mushrooms over after 10 mins.) until mushrooms are fully cooked and tomatoes are slightly browned. (Broil for the last couple of minutes if you like your tomatoes more charred).
Cut buns in half, place bottom layer on a plate. Assemble burgers by layering on the bun, one Portobello mushroom, a slice of Provolone cheese (if using) and top with half of the caramelized tomatoes and top half of bun. Add any garnish you like (lettuce, onions etc.).