Grate zucchini on the fine side of a box grater. Place in a clean kitchen towel and squeeze firmly over the sink to remove as much moisture as possible. You want about 1 cup packed, well-drained zucchini. This step is crucial - wet zucchini makes soggy burgers.

In a large bowl, combine the squeezed zucchini, ground turkey, garlic, scallions, Parmesan, egg, Italian seasoning, salt, and pepper. Use your hands or a fork to mix gently until just combined. Do not overmix or the burgers will become tough.

Divide the mixture into 4 equal portions and shape into patties about 3/4 inch thick. Make a slight indentation in the center of each patty with your thumb - this helps them cook evenly and prevents doming.

Heat olive oil in a large skillet over medium heat until shimmering. Add patties and cook for 5-6 minutes per side, until deeply golden brown and an instant-read thermometer inserted in the center reads 165°F. The zucchini keeps these incredibly moist, so don't worry if they look dark.

Transfer cooked burgers to a plate and let rest for 3 minutes. This allows juices to redistribute so the burgers stay juicy when you bite in.

Serve burgers wrapped in lettuce leaves with tomato and avocado slices. Spread a little mayo or Greek yogurt on the lettuce if desired. These are also excellent cold the next day, sliced over a salad.