01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together flour, baking powder, and salt until well blended.
03 - In a large bowl, beat softened butter and granulated sugar together until light and fluffy, approximately 2-3 minutes.
04 - Beat in the egg and vanilla extract until fully incorporated into the mixture.
05 - Gradually add the dry ingredients to the wet ingredients, mixing just until a cohesive dough forms.
06 - Divide dough in half, flatten into disks, wrap tightly in plastic wrap, and refrigerate for 30 minutes.
07 - On a lightly floured surface, roll out dough to 1/4-inch thickness. Cut out cookies using round or flower-shaped cutters.
08 - Arrange cookies 2 inches apart on prepared baking sheets. Bake for 10-12 minutes until edges are lightly golden.
09 - Let cookies rest on baking sheets for 5 minutes, then transfer to wire rack to cool completely.
10 - Beat softened butter until smooth and creamy. Gradually add sifted confectioners sugar, mixing thoroughly after each addition.
11 - Add milk, vanilla extract, and salt. Beat for 2-3 minutes until fluffy and smooth. Add additional milk 1 teaspoon at a time if needed for piping consistency.
12 - Divide buttercream into separate bowls. Tint each portion with gel food coloring to achieve desired shades.
13 - Fit piping bags with small star, petal, and leaf tips. Fill each bag with colored buttercream.
14 - Pipe flowers and leaves onto completely cooled cookies using decorative tips.
15 - Allow decorated cookies to rest at room temperature until buttercream firms slightly before serving or storing.