Preheat oven to 450°F. For the Oven Roasted Tomatoes, place tomato halves, cut sides up, in foil-lined shallow baking pan sprayed with no stick cooking spray. Drizzle with oil and vinegar then sprinkle with pepper. Roast 25 to 30 minutes or until tomatoes soften and begin to brown.
For the Miso Mayonnaise, mix all ingredients in small bowl until well blended. Cover. Refrigerate until ready to serve.
For the Sautéed Mushrooms and Onions, heat oil in large skillet on medium heat. Add onions; cook and stir 6 minutes or until tender. Add mushrooms; cook and stir on medium-high heat 10 minutes or until onions are caramelized and mushrooms are tender. Keep warm.
For the Burgers, mix ground beef, fish sauce and minced garlic until well blended. Shape into 4 patties. Grill over medium heat 4 to 6 minutes per side or until burgers are cooked through (internal temperature of 160ºF).
Serve burgers on rolls topped with Sautéed Mushrooms and Onions, Oven Roasted Tomatoes and shaved Parmesan cheese, if desired. Serve with Miso Mayonnaise.