01 - In a large mixing bowl, combine shredded cooked chicken, buffalo wing sauce, mozzarella cheese, blue cheese if desired, celery, green onions, garlic powder, and black pepper. Mix until evenly distributed.
02 - Place an egg roll wrapper on a clean surface with one corner facing you. Add approximately 2 to 3 tablespoons of filling in the center. Fold the bottom corner over the filling, tuck in both sides, and roll tightly. Brush the top corner with beaten egg and seal the roll.
03 - Continue to fill and roll the remaining wrappers until all filling is used. Place assembled egg rolls seam-side down.
04 - Pour vegetable oil into a heavy-bottomed pot to a depth of 2 inches. Heat to 350°F (175°C), monitoring with a thermometer.
05 - Working in batches, fry egg rolls for 3 to 4 minutes per batch, turning as needed until golden brown and crisp. Remove with tongs and drain on paper towels.
06 - Arrange egg rolls on a platter and serve warm with ranch or blue cheese dressing on the side for dipping.