Kalim’s favorite food is listed in his profile as “coconut Juice.”
He says, “As long as I can dance, sing, and drink coconut juice, that’s all I need in life!”
While there has maybe been not yet any official explanation for why Kalim’s favorite food is coconut juice, but I have read that it was once considered to be an effective way to neutralize poison:
Up to the modern era, the coconut was claimed to have magical curative powers. It was thought to indicate the presence of pathogenic ingredients or poisons by frothing or changing colour. In a best-case scenario, it would even neutralise the poison. The owner of a coconut thus had on hand an ‘aid against unseen poisoners’.
Twisted Wonderland Reference Note 