- 1 cup (2 sticks) unsalted butter, plus more for pans
- 3 cups all-purpose flour
- 1 tablespoon baking powder
- 1/2 teaspoon salt
- 2 cups granulated sugar
- 4 large eggs
- Finely grated zest of 1 lemon
- 1 teaspoon pure vanilla extract
- 1 cup buttermilk
- 2 recipes <u>Swiss Meringue Buttercream</u>, tinted to desired shade with gel-paste food coloring
- Edible glitter dust
- Confectioners' sugar
- Preheat oven to 325 degrees. Butter six 4-by-2-inch round cake pans, line with parchment, and butter parchment; dust with flour, tapping out excess. Whisk together flour, baking powder, and salt in a medium bowl.
- With an electric mixer on medium speed, beat butter and granulated sugar until pale and fluffy, 3 to 5 minutes. Add eggs, 1 at a time, beating well after each addition. Mix in zest and vanilla. Add flour in 3 batches, alternating with 2 batches of buttermilk; mix until just combined.
- Divide batter among prepared pans. Bake until golden brown and a cake tester comes out clean, about 30 minutes. Transfer pans to wire racks to cool completely.
- With a serrated knife, trim tops of cakes to level; split horizontally to make a total of 12 layers.
- Spread 1/2 cup buttercream on each side of 6 bottom layers, and top with remaining layers. Spread a thin layer of buttercream over each cake to form a crumb coat; refrigerate until firm, about 30 minutes. Spread a second coat of buttercream over each cake; smooth with an offset spatula. Refrigerate 30 minutes (or up to 2 days).
- Set cakes on a wire rack set over a piece of parchment. Stir together edible glitter dust with confectioners' sugar to achieve desired color; the more sugar used, the lighter the hue.
- Cut strips of acetate to preferred width (ours are 1/2-inch wide) and rest them on top of the cakes to create a design. Parallel stripes are the easiest. You can also crisscross stripes, or cover half the cake to create a half-moon. Sift glitter dust over each cake. Carefully lift pieces; reuse to decorate remaining cakes.
Cut sheets of acetate, available at art-supply stores, into strips, then place the pieces atop chilled frosted cakes (you'll need very smooth surfaces). Dust the cakes with edible glitter dust before carefully removing the stencils to reveal the designs.