Suggest Healthy Diet Plan That Helps In Relieving Pain Due To Gall Bladder Stones

Hello, I have a question regarding gall bladder stones. Is it ok to eat mashed potatoes? I realized after I ate a small portion my tummy started to hurt. I threw the dish away. I did sprinkle a very very small amount of shredded cheese and exactly 4 little onions sliced up. Is this what caused the pain??