Heat grill and slice green tomatoes about 1/4 inch thick. In medium bowl, combine oil, garlic, brown sugar, black pepper and fish sauce (or soy sauce or Worcestershire) Add green tomatoes slices to bowl and evenly coat all the slices with the marinade. Grill each side of the tomato till your desired texture (about 2-4 minutes on each side). How thick you slice your tomato will determine how long it cooks. Serve as a side dish, on burgers or chopped in a salad