As in, what's something you loved as a kid, found cringe as you get older, then gained a new appreciation for as an adult? Here are some of mine:

• Pokemon. I expect this will be a common one. It's got cute creature designs and fun tactical battling, and since I've outgrown my shame at liking cute things, I'll happily keep coming back to it.
• Yu-Gi-Oh. I still don't much care for the CCG (I'm opposed on principle to any game where your ability to win largely depends on how much money you're willing to sink into it), but the anime bursts with dorky charm and the video games are fun. A setting where reincarnated ancient sorcerers and billionaires are stone-dead serious about a children's card game is also a nice break from the modern plague of "well that just happened" Marvel soy banter.