Paddle her.

You take the paddle out of the bag and swing it a few times, getting a feel for its heft. You pull her skirt out of your way and admire her naked ass, which is quite delectable. You stand over her and crack the paddle down hard on her left buttock. She makes an audible wince through the gag in her mouth.

You crack the paddle down again on her right buttock and she grunts. You admire the reddening that's starting and then get down to business in earnest, taking out all your pent-up frustrations on her defenseless upturned ass. She grunts in pain throughout, occasionally crying out and by the end she is clearly sobbing.

You put the paddle down and pause to admire your handiwork.