I observed that a couple of users have searched about the food that can be taken on Sivaratri (Shivaratri or Shivratri). It is believed that if a devotee observes a Sivaratri Vrata, he will be cleansed from all sins and will attain the abode of Siva after his death. Generally the Sivaratri fast is observed in the following manner.
A Sivaratri fast continues all through the day and night. Most people observing fast consume a mid-day meal consisting of non-cereal food. The items that are an absolute no-no are non-vegetarian food, onion, garlic, turmeric and ginger. Many people stick to a fruits only diet. No meal is eaten at night (i.e. after sunset). It is only in the following morning that a devotee breaks the fast by consuming the food offered to Lord Shankar.(prasadam or prasad)
Maha Sivaratri / Maha Shivaratri a.k.a Great night of Lord Siva