먹었던 치킨생각나
This means, "when I ate, I thought of chicken," right? But what is the subtext? I wanted to eat chicken instead? It tasted like chicken? I thought "I should eat chicken later?" I wished it was chicken?

Or could it be all of them until you understand the context?

Question

먹었던 치킨생각나
This means, "when I ate, I thought of chicken," right? But what is the subtext? I wanted to eat chicken instead? It tasted like chicken? I thought "I should eat chicken later?" I wished it was chicken?

Or could it be all of them until you understand the context?

Answer

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.

Answer

The meaning of this sentence is "I remember the chicken that I ate".

I guess the hidden meaning of this is "I want to eat chicken again" because you will think of the chicken you ate when you are hungry and crave for it again. :D