Heat oven to 400°F. Line bottoms of three 9-inch-round cake pans with waxed paper. Coat pans and waxed paper with nonstick cooking spray. Coat baking sheet with spray.
Combine flour, sugar, baking powder, baking soda, buttermilk powder and salt in food processor. Whirl to mix. Add butter. Pulse with on-and-off motion until mixture is texture of fine meal. With motor running, add milk through feed tube until mixture just comes together.*
Divide dough into 4 equal batches. Pat 3 batches into three 9-inch rounds on floured waxed paper. Invert rounds into prepared pans; pat out dough evenly in bottom of pans.
Roll remaining batch of dough on floured waxed paper with floured rolling pin to 3/8-inch thickness. Place in freezer for 15 minutes to chill. Cut out 2-1/2-inch heart cookies with cookie cutters. Cut out cupid cookie, tracing pattern at left, or enlarge cupid pattern on photocopy machine one-third to one-half larger. Place cookies on prepared baking sheet.
Bake layers at 400°F for 10 minutes. Invert onto wire racks to cool; remove waxed paper. Bake cookies at 400°F for 8 minutes or until golden. Transfer to racks to cool. Drizzle round layers with melted chocolate if desired.
Thickly slice berries. Beat cream, sugar and vanilla in medium-size bowl until soft peaks form.
Place one shortcake layer on serving platter. Place half the berries evenly over the layer. Spread evenly with 1 cup cream. Top with second shortcake layer, remaining berries, 1 cup cream, remaining shortcake layer and remaining cream. Refrigerate.
Stir powdered sugar and 2-1/2 teaspoons of the water in small bowl until good spreading consistency. If frosting is too thick, add water, 1/4 teaspoon at a time. Divide icing into batches; tint with food coloring as desired.
Decorate cookies with icing as desired. Let air-dry. Arrange on top of cake as pictured.
To prepare dough by hand, cut butter into flour mixture with pastry blender or 2 knives held scissor-fashion, until mixture is texture of fine meal. Drizzle in milk, tossing with a fork, until mixture just comes together.