Clean four portobello mushrooms, remove and discard stems. Brush buttons with olive oil; both sides.
Mix 1 clove of garlic; crush and break up, salt, and pepper. Sprinkle mix on mushrooms then grill rounded sides down 9 minutes with grill closed or until they are tender and hot.
Turn them once while grilling. Thinly slice a round of brie cheese and put aside some fresh arugula; about 1/2 cup, and some tomatoe slices.
Take mushrooms off grill, place one slice of the cheese, some arugula, a couple of the tomato slices, and complete the dish with sprinkling some olive oil over the top. enjoy.