Start by putting two packs of vanilla pudding mix in a bowl. Add two cups of milk to the pudding. Stir it with a large plastic or wood spoon until it is really creamy. Next you will add 8 ounces of sour cream and stir it in with your spoon. After it is well mixed, stir in half of a container of whipped cream (about 4 ounces). In the bottom of another bowl, put 1-2 sliced bananas and some nilla wafers. Take the mixture that you have made in the other bowl and spread it out on top of the wafers and bananas. Spread the remaining cool whip from the container as a last layer on top of the mix. Finally, top the mixture off with a layer of nilla wafers. There you have it: a great banana pudding!