Whisk together flour, baking powder, and salt in a medium mixing bowl.

In a stand mixer fitted with a paddle attachment, cream the softened butter and granulated sugar at medium speed until light and aerated.

Add the egg, milk, and vanilla extract to the butter mixture and beat until fully incorporated.

Reduce mixer speed to low and gradually add the dry ingredients until a cohesive dough forms.

Divide the dough into two equal portions, wrap in plastic film, and refrigerate for at least 60 minutes.

Preheat oven to 375°F (190°C) and line baking sheets with parchment paper.

Roll out chilled dough on a lightly floured surface to a consistent 1/4-inch thickness.

Cut into Easter shapes using egg, bunny, or flower cutters and transfer to prepared baking sheets.

Bake for 7 to 9 minutes until the edges are just set but not browned.

Cool cookies completely on a wire rack before decorating.

Whisk confectioners' sugar, meringue powder, and water for 5 minutes until stiff peaks form to create royal icing.

Tint icing with food coloring and decorate the cooled cookies.