Cut the red onion into thin slices and the tomato and cucumbers into thin slices. Cut the courgette into long slices along the length with a mandoline.
Grill the onion, zucchini and bread slices on the BBQ until they have nice grill marks. Then grill the burgers on both sides.
Brush both sides of the sandwich with Hela Burger Sauce. Top with lettuce, burger, red onion, zucchini, tomato and cucumber. Serve with the chips.