2. Chop 10 of the basil leaves. Mix together with the oil, garlic, salt and pepper.
3. Sprinkle the cheese on the bottom of the pie shell. Arrange the remaining 10 whole basil leaves on top of the cheese.
4. Brush each slice of zucchini and tomato with the basil-garlic oil. Arrange the zucchini and tomato slices alternately, overlapping by half, in a single layer in the pie shell. Brush the entire layer again with the basil-garlic oil.
5. Bake until the vegetables are warmed, about 8 to 10 minutes. Serve warm.