Cut mozzarella into 1/2" sticks, about 3" long.
Mix eggs and milk in one bowl
Mix bread crumbs and parmesan in another bowl
Dredge each stick in eggs and bread crumbs, then eggs again and bread crumbs again. Place on parchment paper on baking sheet.
Once all sticks are dredged, place in freezer for one hour or more (overnight is fine).
Heat oil 1" deep to 350°F. Fry sticks for 90 seconds, then remove to paper-towel lined plate to drain.
Serve hot with marinara sauce.
Alternative 1: Bake in countertop convection oven at 390°F for 6–8 minutes after spraying with oil.
Alternative 2: Bake in conventional oven at 400°F for 10–12 minutes after spraying with oil.