Place the mushroom caps, smooth side up, in a shallow dish. In a small bowl, whisk together vinegar, oil, basil, oregano, garlic, salt, and pepper. Pour over the mushrooms. Let stand at room temperature for 15 minutes or so, turning twice.
In a lightly oiled pan, add the mushroom caps along side the onion slices and saute 5 to 6 minutes, turn caps saute another 4 to 5 minutes. Then remove from pan and set aside.
In the same pan, add Sweet Earth Teriyaki Veggie Burgers and heat for 3 to 4 minutes per side.
On a toasted wheat bun (or roll of choice), add your favorite condiments, lettuce. Then add veggie Burgers on one end and ‘bello caps on the other. Take a beauty shot like this one, then close and enjoy!
Serve with asparagus or other spring vegetable of choice!