In a large bowl, combine chopped spinach, cream cheese, shredded mozzarella, sour cream, and grated Parmesan. Add garlic powder, onion powder, salt, and black pepper to taste. Mix until smooth.

Take mozzarella string cheese sticks and cut in half. Scoop spinach mixture to wrap around each stick, sealing well.

Set up a breading station with flour, beaten eggs, and panko breadcrumbs in three shallow dishes.

Dip each stick in flour, then in beaten eggs, and finally coat well in breadcrumbs.

Heat about an inch of vegetable oil in a skillet over medium heat until it reaches 350°F.

Fry the sticks for 2-3 minutes on each side until golden brown. Drain excess oil on paper towels.

Serve warm with marinara sauce or your favorite dipping sauce.