Prepare the ingredients as instructed above.
Mix the ground beef with worchestershire sauce, salt and pepper until combined. Form into patties.
Heat a grill or grill pan over medium heat. Grill the patties on one side for 3 minutes, then flip and cook to desired temperature (see below). Place a slice of cheese on each patty and allow it to melt.
Optional: Toast the hamburger buns cut-side down on the grill until golden brown.
Assemble the burgers by layering the bun with lettuce, tomato slices, beef patty, and onion. Top with the other half of the bun. Serve with ketchup.
To make the mango lassi, blend the frozen mango, plain yogurt, milk, ground cardamom, and sugar until smooth. Taste and adjust sweetness as needed.
Serve the burger with carrots and hummus, and mango lassi.