Make the sauce by whisking all the ingredients together in a small bowl until well combined. Set aside in the refrigerator until ready to use.

Brown the beef in a large nonstick pan set over medium-high heat, breaking it up with a spoon, until browned and cooked through with no pink. Drain off excess fat, then season with salt and black pepper. Allow it to cool slightly.

Divide the lettuce between salad bowls, then top evenly with ground beef, cheese, onions, pickles, and tomato. Drizzle the salad with the Big Mac sauce, garnish with sesame seeds, and serve.