Toast the panko bread crumbs in a frying pan with olive oil over medium heat, stirring often and until golden brown. (About 10 minutes) Spread crumbs in a shallow dish and set aside.
Combine flour, salt, pepper and garlic powder in a shallow dish. Set aside.
Mix egg whites and water in a shallow dish. Set aside.
Pound chicken breasts flat, between two pieces of wax paper, until about a ¼ inch thick. Lay each chicken breast flat. Place a piece of ham and cheese in the middle. Fold in edges of chicken and roll up.
Dredge chicken in flour mixture, shake off excess.
Using tongs, coat chicken in egg wash allowing excess to drip back into the dish to ensure an even coating.
Now, dip chicken in panko bread crumbs, pressing to form an even coat.
Place chicken on a wire rack over a baking sheet (this prevents the bottom of the chicken from getting soggy). Repeat steps for each chicken breast.
Spray the chicken with vegetable spray. Place in a 475 degree oven on the middle rack and bake approximately 20 to 25 minutes, depending on the size of the chicken breast.