1. In a medium bowl, whisk together egg, salt and pepper.
2. Place ground beef and bread crumbs into the mixture. Mix with hands until well blended.
3. Form into four patties, about 3/4 inch thick.
4. In a large skillet heat 1 tablespoon vegetable oil over medium-high / high heat. Add the patties and cook until they are well browned on both sides.
5. Prepare the vegetables.
6. On each half a hamburger bun place 1/2 leaf of lettuce, top lettuce with patty.
7. Spoon 1 teaspoon mustard over each patty. Top each with a slice of American cheese, 2 slices of tomato, onion.
8. Spoon 1 teaspoon mayonnaise over burgers, add a couple of pickle slices and cover with the other half a hamburger bun.