Place baguette slices on an ungreased baking sheet. Broil 3-4 in. from the heat until toasted, 1-2 minutes on each side.
Meanwhile, carefully remove waxed coating from cheese round. Using a 3-in. biscuit cutter, press into the center of cheese, but not all the way through. Scoop out center, leaving a 1/4-in. shell; set shell aside.
Place the tomato, basil and removed cheese in a small microwave-safe bowl. Cover and microwave on high until cheese is melted, about 1 minute. Stir until combined; pour into shell. Serve with baguette toasts.