Slice each chicken breast horizontally to create 4 thin cutlets. Gently pound to an even thickness if needed. Season both sides with kosher salt, black pepper, and garlic powder.

Place the flour in one shallow bowl. In a second bowl, whisk the eggs with the water. In a third bowl, combine the panko breadcrumbs and finely grated Parmesan.

Dredge each cutlet in flour, dip in the egg mixture, and coat well in the panko-Parmesan mixture. Transfer to a plate or tray and let rest for 5 minutes.

In a mixing bowl, whisk together the mayonnaise, Greek yogurt, lemon juice, Dijon mustard, grated garlic, grated Parmesan, and black pepper.

Heat about 1/2 inch of neutral oil in a large skillet over medium heat. Fry the chicken cutlets in batches for 3 to 4 minutes per side, until golden brown and cooked through. Transfer to a rack or paper towel-lined plate.

Add the chopped romaine to the Caesar dressing and toss until lightly coated.

Lightly toast the sandwich rolls if desired. Place one crispy chicken cutlet inside each roll.

Top with the dressed romaine and shaved Parmesan. Finish with extra black pepper if desired and serve immediately.