Cheeseburger Pie

Name: Cheeseburger Pie
Ingredients: 1 tablespoon neutral oil, such as grapeseed or vegetable oil; 1 pound ground beef; 1 clove garlic, finely chopped; 1 small white onion, chopped; 3 tablespoons Worcestershire sauce; 2 tablespoons ketchup; 2 tablespoons mustard; Kosher salt; Freshly ground black pepper; 1 cup shredded cheddar; 4 slices white American cheese; 1 egg beaten with 1 tablespoon water; 2 teaspoons sesame seeds; Toppings; 3 tablespoons mayonnaise; 1 medium head iceberg lettuce, shredded; 1 medium tomato, finely chopped; Dill pickle spears