Divide the ground beef into two 150-gram balls and shape them into patties.
Heat a frying pan over medium-high heat and season the patties with salt.
Add vegetable oil to the hot pan and then add the patties. Use a large spatula to flatten them and cook for 2 minutes or until cooked halfway through before flipping.
Cook patties for another minute and then set aside to cool completely.
Break up the cold patties into a large bowl and add cheese, onion, pickles, mustard, and ketchup. Stir well.
Lay one spring roll wrapper on a clean work surface with a corner pointed towards you and add two tablespoons of the mixture towards the bottom corner.
Fold the bottom corner over the mixture, fold the side corners over the mixture, and then roll towards the final corner. Use a little egg wash to seal the top corner and set aside. Repeat until all the filling has been used.
Preheat the deep fryer to 180⁰C and gently place the spring rolls into the hot oil.
Fry for 3-4 minutes or until golden brown, gently stirring with a metal slotted spoon to cook them evenly.
Use a metal slotted spoon to carefully remove the spring rolls and place them on a plate lined with paper towel to drain for a few minutes.