Cook the Beef:

In a skillet over medium heat, cook the ground beef and diced onions until the beef is browned and the onions are translucent. Drain excess fat.

Stir in the diced pickles, shredded cheddar cheese, ketchup, and mustard. Season with salt and pepper to taste. Allow the mixture to cool slightly.

Assemble the Egg Rolls:

Lay out an egg roll wrapper with one corner pointing toward you. Place about 2 tablespoons of the beef mixture in the center of the wrapper.

Fold the bottom corner over the filling, then fold in the sides. Roll up the wrapper tightly, sealing the top corner with a bit of water. Repeat with remaining wrappers and filling.

Fry the Egg Rolls:

Heat oil in a deep fryer or large pot to 350°F (175°C). Fry the egg rolls in batches for 3-4 minutes, or until golden brown and crispy. Use a slotted spoon to transfer the egg rolls to a paper towel-lined plate to drain excess oil.

Serve:

Serve the egg rolls hot with dipping sauces such as ketchup, mustard, or ranch dressing.