Measure flour into a pie plate. In another pie plate combine panko, Parmesan, parsley, red pepper flakes and salt and pepper, to taste. In a third plate add eggs and water. Dredge the zucchini in the flour, followed by the egg and finally in the panko.
Working in batches, place the breaded zucchini slices in the hot oil and fry until golden brown, 3 to 4 minutes. Drain on a paper towel lined sheet tray and immediately season with salt and pepper. Serve alongside the zucchini.
For the sauce:
Add all the ingredients into a serving bowl and mix until incorporated. Cover with plastic wrap and let flavors marinate for at least 1 hour.