The most important point is to keep portions under control by buying single-serving bars if possible or breaking off a serving and putting the rest of the bar outofsight so youare not tempted to eat more than one serving.
But this mini-game embraces the Hitman ethos by giving you points for headshots, as well as taking out targets such that their bodies are disposed outofsight: off the edge of the building, into a pond, and even down an elevator shaft.