Two for me: coffee and sushi.
I didn’t start drinking coffee until I was in my middle 20’s. When I tried it as a younger person I didn’t like it because it was so bitter. It wasn’t until I was on a cruise (with my wealthy extended family) I had a fancy boy cappuccino and I was like “hot damn, this bitter water is actually good!” Now I drink at least 4 cups of coffee every moring.
I tried sushi in my teens and absolutely hated it, I remember gagging at the taste of the raw fish. Like coffee it wasn’t until years later as an adult I tried sushi again at a Japanese place in town and I was like “damn, this raw fish is really tasty!” Now sushi is a regular staple takeout food for me.
Olives, blue cheese, olive oil (tasted way too strong and bitter), garlic, most seafoods. Pretty sure there were many others, but have forgotten.