Mix it, Stretch it, Boil it Up! Burn Copper Pot, Burn!

is episode 168 of the original Naruto anime.

Synopsis
Naruto, Chōji and Sakura volunteer to help Teuchi, whose daughter Ayame was kidnapped by a band of cooking-nin led by Hakkaku. To save her, they must come up with the ultimate ramen recipe. Teuchi tries to teach them how to cook, and the three take advantage of their ninja techniques to make the perfect bowl of ramen. When they rescue Ayame, she has grown fat due to being unable to resist the cooking ninjas' food. To bring her to her regular self, she eats Teuchi's diet ramen that appears to be designed to make people lose weight from eating it. However, in the end it shows Teuchi had eaten the diet ramen and ended up losing too much weight.