Preheat the oven to 350°F (175°C) and line baking sheets with parchment.

In a stand mixer fitted with the paddle attachment, cream the softened butter and sugar until pale and fluffy.

Add the egg whites, princess cake emulsion, and vanilla; mix on low just until incorporated, scraping the bowl as needed.

In a separate bowl, whisk together the flour, baking powder, and salt, then add to the mixer on low until the dough comes together—avoid overmixing.

Gently fold in the sequin sprinkles with a spatula.

Scoop about two tablespoons of dough per cookie onto the prepared sheets, leaving space between each.

Bake for 12–15 minutes, until edges are lightly golden and centers look set.

Cool completely on the baking sheet before frosting.

Beat the softened butter and cream cheese together until smooth.

Add half the powdered sugar along with the vanilla and milk; mix on low until combined.

Add the remaining powdered sugar, then increase to medium and whip until light, fluffy, and silky.

Tint with pink gel food coloring to your desired shade.

Transfer the frosting to a piping bag fitted with a round or star tip.

Pipe a spiral onto each cooled cookie, then immediately add more sequin sprinkles so they adhere.

Let the frosting set for a few minutes before serving.