Pull grapes from stems and wash. Dry with paper towels once cleaned.
In separate bowl, combine cream cheese, sour cream, sugar and vanilla. Thoroughly mix together with a stand or electric mixer.
Pour over top of grapes and stir together. Chill in refrigerator for at least 2 hours before serving.
Toast chopped walnuts in pan on stove on medium-low heat for about 3-5 minutes or until the nuts start to get fragrant. Watch the nuts closely so they don’t burn.
When getting ready to serve, remove from refrigerator and top each individual serving with the toasted walnuts.