In small bowl, combine flour and salt; set aside. In large bowl, beat butter until light and fluffy; gradually add
sugar, beating well. Add egg yolk and vanilla; mix well.
Slowly add flour mixture, beating on low speed until incorporated. Increase speed to medium and beat 2 minutes. Form dough into 3 disks, about 1 in. thick; wrap in plastic wrap. Chill 1 hour or until firm enough to roll.
Preheat oven to 350°F. Line cookie sheets with parchment paper.
On floured surface, roll out dough 1/4 in. thick (keep remaining dough in refrigerator until ready to roll). Cut with star cutter; place on prepared cookie sheets. Place cookies in freezer for 15 minutes before baking. Form scraps into a disk, chill at least 30 minutes and reroll.
In small bowl, whisk together egg and cream. Remove cookies from freezer and brush lightly with egg mixture. Sprinkle with Sparkling Sugar. Bake 10-12 minutes or
until light golden brown. Remove to cooling grid and cool completely.