Lightly toast the bread in a toaster or under a preheated hot grill. Meanwhile, mix the grated carrot with the mayonnaise and season with pepper.
Spread the hummus on 1 slice of the toast and top with half the tomato slices and rocket.
Place a second slice of toast on top and spoon over the carrot mixture. Top with the remaining tomato and rocket. Place the remaining slice of toast on top and press down gently. Cut the sandwich in half or quarters and secure with cocktail sticks. Serve immediately.