Mix 70g lean minced beef with a quarter of a finely diced onion and a finely grated carrot. Season with a dash of Worcestershire sauce. Form into a burger. Grill for 4 min each side. Serve with in a wholemeal burger bun, lightly toasted on the inside sides, with some low fat mayonnaise, tomato and lettuce alongside a mixed salad drizzled with balsamic vinegar.