Trying to remember a holiday episode

Years ago possibly late 80's early 90's there was a Christmas party with guests showing up and spiking the egg nog. Later, someone sticks his cup in the egg nog, takes a drink, and says "This is some kick ass nog!" I think it was Meshach Taylor who said this. My dad thinks it was Tom Poston on a Newhart episode. I have tried to figure out which show this could have been, and looked through a lot of episode descriptions. If anybody has an idea I will be much obliged. I know it's not much to go on.