When I read the sentence "먹었던 치킨 생각나", I thought "I'm thinking about the chicken I had before.". I'm not sure what you really wanna say. I need the context or the explanation of the situation.
When I ate, I thought of chicken. = 나는 먹을 때, 치킨을 생각했어.
I wanted to eat chicken instead. = 나는 치킨을 먹고 싶었어.
It tasted like chicken. = 치킨 맛이 나.
I thought "I should eat chicken later." = 나중에 치킨을 먹어야겠다고 생각했어.
I wished it was chicken. = 이게 치킨이었으면 좋았을 텐데.