Combine the panko, Italian breadcrumbs, garlic powder, black pepper, and salt in a third shallow dish.
Roll each of the halved cheese sticks in the flour, making sure to cover all sides including the ends. Then dip each into the egg mixture and roll in the breadcrumbs. Place on the baking sheet. Repeat with remaining cheese sticks.
Then dip each cheese stick back into the eggs and roll in the breadcrumb mixture. Return to the baking sheet and freeze for 30 minutes.
Preheat the oven to 375 degrees.
Remove the cheese sticks from the freezer and spray with cooking spray.
Bake the cheese sticks for 10 minutes, checking frequently to make sure the cheese is not oozing from the sticks.