Chocolate can be fed to Zen Gardenplants when fully grown and Stinky the Snail. When fed to Stinky, it will move much faster and will not fall asleep until one hour. When utilized on plants, chocolate will cause them to drop money at approximately four times the normal rate. Their animation will speed up too.
Once ten pieces of chocolate have been amassed, no more chocolate will appear. However, if nine pieces of chocolate are in the player's inventory and two or more pieces are spawned in different levels and then are collected, then eleven or more pieces of chocolate can become available at once. The player can also hack using Cheat Engine to earn as many they want to in game, up to the integer overflow number (214,748,366). Trying to go over will lead to you having negative chocolates. To be exact, -214,748,363.