Chop half of the nuts of your choice and leave the other half for garnish.
Place the crushed pineapple in a bowl and add the pistachio Jell-O instant pudding mix. Mix until well combined.
Add the miniature marshmallows and chopped nuts. Mix with a spatula until well combined.
Now add the Cool Whip to the pudding mixture and gently fold it into the mixture with a spatula.
Transfer the mixture into glasses and chill for at least 60 minutes in the refrigerator. Once chilled, serve the Watergate salad cold, garnished with the remaining nuts.