Hahaha, gold right here.
Some chick asked me out through drive-thru with this technique and since then it has been my official method for asking out girls who I've barely met.
(After some casual conversation)
You: Hey [name], would I sound desperate if I asked you out?
Girl: Yes...
You: Not exactly the answer I was hoping for, but I'm going to ask you anyways. Can I take you to dinner this Saturday?
Of course, if she says you wouldn't sound desperate, just don't act like an idiot and you're probably alright. It's a little corny, but it's funny and unexpected enough to work a fair amount.