I took my first pie a few weeks ago when I lost a bet to my wife. I've always wanted to be pied. I absolutely loved it. She seemed disinterested but when she pied me she enjoyed it for sure. I thought this would be our thing. I was so excited, but now even when I drop hints she chuckles but doesn't seem interested in actually participating (pieing me).
Should I just ask her to pie me when I want to be pied? I mean it's no real trouble to her, just seems like she might think it's strange I'm asking to be pied.
Thank you!

Yeah just ask her. Maybe make it part of foreplay. You need to be upfront about the fact it turns you on.

Seconding piecub.
You need to explain that's it's a fetish you have. It isn't necessarily 'no real trouble' just because you are married. In the long run this is how you get pied whenever you want.

Thank you. I've let her know I find it very erotic and sensual. It wasn't easy to let her know for fear of judgement but I figured it's best, but it didn't change anything.