Step 1 Cut off thick slice (about 1/2 inch/1 cm) at stem end of tomato. Scoop out seeds and centre pulp. Scoop any seeds from tomato slice. Place tomato and tomato slice cut side down on paper towel to drain for about 5 minutes.
Step 2 Whisk egg, basil, salt and pepper in small bowl.
Step 3 Set tomato upright in small microwave-safe bowl. Pour egg mixture into tomato. Sprinkle cheese over egg, if desired. Cover with tomato slice.
Step 4 Microwave on Medium High (70% power) until egg is puffed and just cooked, about 2 minutes. Let stand for 1 minute.