How to Make It
Preheat oven to 350°. Lightly grease (with cooking spray) an aluminum foil-lined 8-inch square pan. Pulse vanilla wafers and next 2 ingredients in a food processor until blended. Add butter; pulse until blended. Press mixture into bottom of pan.
Bake at 350° for 8 minutes or until lightly browned. Reduce oven temperature to 325°. Beat cream cheese and 1/2 cup powdered sugar at medium speed with an electric mixer. Gradually add eggnog, beating at medium speed. Stir in nutmeg, cinnamon, and egg; pour over vanilla wafer mixture.
Bake at 325° for 30 to 35 minutes or until outer 2 inches are set. Cool completely on a wire rack (about 1 hour).
Beat cream at medium-high speed, using whisk attachment, until foamy. Gradually add vanilla and 2 Tbsp. powdered sugar, beating just until soft peaks form.
Remove blondies from pan; discard foil. Cut blondies into squares, and dollop with whipped cream mixture.