Basoda Puja, also known as Sheetala Ashtami, is dedicated to Goddess Sheetala and is celebrated on Krishna Paksha Ashtami after Holi. Sheetala Ashtami, which is more popular in the North Indian states like Gujarat, Rajasthan and Uttar Pradesh, usually occurs eight days after Holi, but it is noticed that people in many places observe it on the first Monday or Friday after Holi.
As per the existing customs, on Sheetala Ashtami day, families should not cook fresh food. So they cook one day before and eat the stale food on this day. Devotees believe that Goddess Sheetala controls diseases like smallpox, chickenpox, measles, etc. and they worship the Goddess to protect them from outburst of such diseases.
In Gujarat, people observe a ritual called Shital Satam just a day before Krishna Janmashtami. Similar to Sheetala Ashtami, Shitala Satam is also dedicated to Goddess Sheetala and no fresh food is cooked by the families on that day.