Slice the mozzarella block into 16 uniform sticks.
Whisk together eggs and milk in a shallow dish.
In a second bowl, mix Italian breadcrumbs, panko, Italian seasoning, garlic powder, onion powder, and Parmesan.
Dip each cheese stick in egg mixture, then press into breadcrumb blend. Repeat dipping once more in egg and crumbs for a triple-layered crust.
Arrange the breaded sticks on a parchment-lined tray and freeze for at least 1 hour to lock in shape.
Heat 1–2 inches of oil in a large, wide skillet over medium heat to 350°F–360°F.
Fry mozzarella sticks in batches (3–4 at a time) for about 1 minute per side, just until golden.
Transfer to a paper-towel lined rack, then finish in a preheated 375°F oven for 3 minutes to ensure extra crispness.
Serve immediately with your favorite marinara or ranch dip.
