- Preheat oven to 325°F.
- Make three slices lengthwise along the zucchini being careful not to slice all the way through.
- Cut mozzarella slices into thirds and place a piece of cheese into each opening in the zucchini.
- Cut prosciutto slices in half and add one piece next to each mozzarella slice.
- Sprinkle with garlic powder.
- Make a loose tent around each zucchini with aluminum foil and bake for 30-35 minutes.