- Preheat oven to 400° F.
- Cut zucchini into ¾-inch slices. Using a melon baller or small spoon, scoop out the insides and discard, leaving the bottom intact. Place zucchini on an ungreased baking sheet; spoon ½ teaspoon crumbled blue cheese into each.
- Combine the Parmesan cheese, basil, and pepper; sprinkle half over blue cheese. Top each with a tomato slice; sprinkle with the remaining Parmesan mixture. Bake at 400°F until cheese is melted, 5-7 minutes. Serve warm.