In A Small Bowl, Combine The Mayonnaise, Mustard, Garlic And Vinegar Until Blended. Cut The Brie Horizontally Into Three Rounds; Cut Each Round Into Eight Wedges. Place English Muffins, Cut Side Up, In A Foil-Lined 15-In. X 10-In. X 1-In. Baking Pan. Broil 3-4 In. From The Heat For 2 Minutes Or Until Lightly Toasted. Spread Muffins With Mayonnaise Mixture. Layer With Ham, Tomato And Cheese Wedges. Broil 3-4 In. From The Heat For 5 Minutes Or Until Cheese Is Melted.