Note: Try to brown without breaking up the meat too much. Get a nice brown sear on the beef, then break apart as little as possible. (You want the meat to resemble a pea in size, and to avoid taco meat consistency).
Add the salt, pepper, and Worcestershire sauce. Stir gently and remove beef mixture from pan.
Add the butter, chopped onions, and green bell pepper into the pan, cooking until browned and caramelized.
Once browned, add the meat back in and combine together.
Let the mixture cool while you prepare your egg roll wrappers and cheese.
Lay wrappers on a flat surface and place a half a slice of American cheese on the wrapper.
Add three tablespoons of the meat mixture on top of the cheese.
Starting from the bottom left pull the corner over the meat, then fold the two sides in.
Wet the edges and roll tightly.
Add the oil to fill the pan about 1-inch high, and set to medium-high heat.
Add 3-4 egg rolls in the pan at once.
Once they have browned, take them out and dry them on a cooling rack or brown paper bag.
Lasha