Double Cheeseburgers, Los Angeles-Style

Name: Double Cheeseburgers, Los Angeles-Style
Cook time: 45 min
Total time: 45 min
Cuisine: American
Ingredients: 1/3 cup mayonnaise; 1 tablespoon toasted sesame seeds; 4 tablespoons unsalted butter, at room temperature; 4 brioche hamburger buns, split; 2 pounds ground chuck, shaped into eight 1/4-inch-thick patties; Kosher salt; Freshly ground pepper; 2 tablespoons olive oil; 8 slices of cheddar cheese; 4 butter lettuce leaves; 4 shiso or sesame (perilla) leaves; 4 thin slices of tomato; 4 thin slices of red onion