In a mixing bowl, combine the shredded corned beef, cabbage, carrot, green onions, garlic powder, and black pepper. Mix well until all ingredients are evenly combined.

Lay an egg roll wrapper on a clean surface with a corner pointing towards you. Place about 2 tablespoons of the filling in the center. Fold the bottom corner over the filling, then fold in the sides and roll tightly to seal. Repeat with remaining wrappers and filling.

Heat vegetable oil in a deep fryer or frying pan over medium-high heat. Once hot, carefully add the egg rolls in batches, frying until golden brown and crispy, about 3-4 minutes per side. Remove and drain on paper towels.

Serve hot with your favorite dipping sauce, such as sweet and sour sauce or mustard.