01 - Whisk together flour, baking powder, and salt in a medium bowl. Set aside for later use.
02 - Beat softened butter and granulated sugar in a large bowl until light and fluffy, approximately 2-3 minutes.
03 - Add egg and vanilla extract to the butter mixture, mixing until fully incorporated.
04 - Gradually incorporate dry ingredients into the wet mixture, mixing just until dough comes together.
05 - Divide dough into two discs, wrap tightly in plastic wrap, and refrigerate for at least 30 minutes.
06 - Preheat oven to 350°F. Line baking sheets with parchment paper.
07 - On a lightly floured surface, roll dough to 1/4-inch thickness. Cut out egg shapes using cookie cutter.
08 - Place cut cookies 2 inches apart on prepared baking sheets.
09 - Bake for 8-10 minutes until edges begin to turn golden. Let cool on baking sheets for 5 minutes, then transfer to wire racks.
10 - Whisk powdered sugar, 2 tablespoons milk, corn syrup, and vanilla until smooth. Add additional milk as needed to achieve thick but drizzle-able consistency.
11 - Divide icing into separate bowls and tint with gel food coloring to create desired pastel shades.
12 - Using piping bags or squeeze bottles, decorate cooled cookies with colored icing. Allow icing to set completely before serving.