[mgsimpleton]

i wasn't very wordy before but let me also add... it is so likely he has total air here that i think your line loses a lot of value. i think air (and i include small pocket pairs like TT or 99 in there) often calls raise pre, sees ace on flop, and tries to take it away. he called a huge reraise preflop and you have the Ac meaning he doesnt have AcKc or something... do you realllllly think he has a flush draw? It is unlikely, imo.

so most likely what i'm doing here is "thinking for a while" and calling, then checking or betting slightly less than half pot on turn (the choice between those two depends on my opponent's tendencies). if you bet and he calls on turn, it is likely he has AQ or flush draw, in which case you can decide bet check call riv or bet for value... most likely he will fold turn but sometimes when you are extra lucky he'll get that inkling to push you off your KK.

edit: didn't see stack sizes. when so short, prolly check turn. logic still applies.