# What You Need:
→ Vanilla sheet cake
01 - 2 1/2 cups all-purpose flour
02 - 2 1/2 teaspoons baking powder
03 - 1/2 teaspoon fine salt
04 - 1 cup (2 sticks) unsalted butter, room temperature
05 - 2 cups granulated sugar
06 - 4 large eggs, room temperature
07 - 1 tablespoon pure vanilla extract
08 - 1 cup whole milk, room temperature
→ Sage green buttercream
09 - 1 1/2 cups (3 sticks) unsalted butter, room temperature
10 - 5 cups powdered sugar, sifted
11 - 2 to 3 tablespoons heavy cream or milk
12 - 2 teaspoons pure vanilla extract
13 - Pinch of fine salt
14 - Sage green gel food coloring, to tint
→ Gold buttercream accents
15 - 1/2 cup reserved buttercream (set aside from the batch)
16 - Edible gold luster dust
17 - 1 teaspoon clear vanilla extract or vodka, optional (to mix with luster dust for painting)
# How To Make It:
01 - Set oven to 350°F. Grease a 12x18-inch sheet pan and line the base with parchment, leaving an overhang for easy removal.
02 - In a medium bowl, whisk together the all-purpose flour, baking powder and salt until evenly combined.
03 - In a large bowl with an electric mixer, beat the unsalted butter and granulated sugar on medium-high until light, pale and fluffy, about 3 to 4 minutes.
04 - Add eggs one at a time, beating after each addition until incorporated. Mix in the vanilla extract.
05 - Add the flour mixture in three additions, alternating with the milk and beginning and ending with flour. Fold or mix on low speed until just combined; avoid overmixing.
06 - Spread batter evenly into the prepared sheet pan and smooth the surface. Bake 28–32 minutes or until a toothpick inserted in the center comes out clean. Transfer to a wire rack and cool completely in the pan.
07 - In a large bowl, beat the butter until creamy. Gradually add the sifted powdered sugar, mixing on low, then increase speed and beat until smooth. Add vanilla and salt, then add heavy cream 1 tablespoon at a time until you reach a spreadable consistency.
08 - Tint the majority of the buttercream with sage green gel coloring to achieve the desired hue. Reserve 1/2 cup of uncolored or lightly tinted buttercream for gold accents.
09 - Using an offset spatula, spread the sage green buttercream evenly over the cooled cake, creating a smooth finish or textured surface as desired.
10 - Mix edible gold luster dust with a few drops of clear vanilla extract or vodka to form a paintable suspension, or blend luster dust directly into the reserved buttercream for a metallic paste.
11 - Pipe details or small accents with the reserved buttercream, then use a food-safe brush to paint the metallic mixture onto piped areas or add gold-highlighted swirls. Finish with sprinkles or celebratory piping as desired.
12 - If clean squares are desired, chill the cake until the buttercream firms slightly, then slice into 24 even portions using a long, sharp knife.
