In a skillet cook ground beef and diced onion over medium heat until browned.
Drain excess grease and season with salt and black pepper.
Stir in ketchup, mustard, and pickle relish.
Place an egg roll wrapper on a flat surface.
Spoon a small amount of the beef mixture onto the center.
Sprinkle shredded cheddar cheese on top.
Fold the sides and roll tightly into an egg roll shape.
Heat oil in a deep skillet to about 350°F (175°C).
Fry egg rolls for 3–4 minutes until golden and crispy.
Remove and drain on paper towels before serving.
