Hi tomcaca, welcome to the board, and enjoy your great car! That sounds uncharacteristic of the car, I've never experienced that. Try the reset of the electronic throttle prescribed in other posts,
Throttle calibration. If that doesn't work, than see if you can recreate it cause you know that if you take it to dealer service first thing they will want to do is try to experience what you did. Also check none of the spark plug cables are loose.