There’s no visible object as reward once you’ve reached Level 10 of Drink Me but you’ll see its special effect once customers drink it. Just like Alice in Wonderland, your customers will shrink when they drink the potion.
Playfish announce this special effect through the Restaurant City fan page in Facebook. Along with the announcement, it gave out free Sugar ingredient to help players start leveling up the Drink Me recipe. Aside from Sugar, other ingredients needed for the recipe are Water, Pineapple, and Chili.
You can get the free Sugar by clicking on this link: http://bit.ly/beA3BU
Be sure to get it as soon as possible because it is available for 24 hours only. The free Sugar ingredient can be used on other recipes, not just for the Drink Me. Free ingredient is always a good thing in Restaurant City.