Hey,
I dunno if it will work, sticking a piece of hash in the middle of a cookie. THC is fat solluable, so wouldnt you NEED to melt it into butter first? I got some hash cookies when I was in Amsterdam, and they will mess you up hard core. Make sure you aren't going to have to drive or operate any complex machinery more complex than a YOYO (lol) because man, it's a powerful high. Good luck with them (but consider making butter, since again, I dunno if just sticking a piece of hash in a cookie will work)
-PM