Make this for your sweetie on Valentine's Day or any day you feel like serving an ambrosial treat. Combine flour, butter, egg and vanilla in a food processor. Pulse until butter is the size of small peas. Add sugar, salt and walnuts and process just until dough pulls together. Remove from bowl and pat into a flat disk. Dust with flour, wrap with plastic wrap and chill for 1 hour. Preheat oven to 375° F. Put dough in a 6-1/2-inch heart-shape tart mold on a baking sheet or a 6-inch French tart pan. Gently pat dough against sides and bottom to a thickness of 1/4 inch. Trim excess dough and cut it into little hearts to bake along with the crust. Cover crust with a piece of aluminum foil, shiny side down. Prick the dough well with a fork through the foil and fill with pie weights or dried beans. Bake in the middle of the oven until crust begins to pull away from pan, 15 minutes. Remove foil and beans. Prick crust again, if necessary, and return to oven until golden, 6 to 8 minutes. Cool crust and hearts on a rack. Spread Silver Palate Raspberry Fudge Sauce over crust. Add raspberries in a single layer, then the hearts. Refrigerate until serving. Serve with softly whipped cream, if desired.