Instructions

Directions:

1. Cut each roll in half and lightly brush each side with olive oil. Set aside. Halve the lemon and brush it with olive oil too. Set aside. You will grill these things toward the end.
2. In a small bowl, combine remaining olive oil and vinegar. Cut zucchini lengthwise into very thin slices, about 1/4 inch. Do the same with the onion if using. Brush sliced veggies with oil and vinegar mixture. Season with salt and pepper.
3. Heat grill until coals are medium-hot and cook veggies on uncovered rack for 2-3 minutes on each side or until tender. We have a small grill so we had to do this in batches but it worked out fine because we put the finished veggies on a plate covered in foil so they stayed hot.
4. During the last 3 minutes of grilling, add the rolls and lemon to the grill, oiled sides down. Grill until they’re starting to slightly charred.
5. Assemble sandwich by placing zucchini and onion on rolls, top with tomato if desired, sprinkle feta on top and drizzle with remaining oil and vinegar mixture. This is where we added more vinegar to the buns for some extra tang. Lastly, squeeze juice from grilled lemon and top with other half of grilled bun.

Source: Better Homes and Gardens August 2009