Create the Cookie Dough
In a medium bowl, whisk together the flour, baking powder, and salt. In a separate large bowl, use a mixer to beat the softened butter and granulated sugar until light and fluffy, about 2-3 minutes. Beat in the egg and vanilla extract until just combined. Reduce the mixer speed to low and gradually add the flour mixture, mixing only until a soft dough forms.

Chill and Roll the Dough
Divide the dough in half. Flatten each half into a 1-inch thick disk and wrap tightly in plastic wrap. Refrigerate for at least one hour. Chilling the dough solidifies the butter, which is the key to preventing the cookies from spreading while baking.

Cut and Bake Your Cookies
Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper. On a lightly floured surface, roll one disk of dough to a ¼-inch thickness. Use a 2.5-inch round cookie cutter to cut out your shapes, placing them about one inch apart on the prepared baking sheets. Bake for 10-12 minutes, or until the edges are just lightly golden. Allow the cookies to cool completely on the baking sheet before decorating.

Prepare the Royal Icing & Decorate
While the cookies are cooling, prepare the icing. In a large bowl, whisk the confectioners’ sugar and meringue powder. Add the water and beat with a mixer on high speed until glossy and stiff peaks form. For flooding, thin out about two-thirds of the icing with a bit more water. Outline and then fill each cookie with the white flood icing. While the icing is still wet, pipe a colored circle for the iris and immediately place a mini chocolate chip or sugar pearl in the center for the pupil. Let the cookies dry for about an hour before using a fine-tipped toothpick or food-safe brush to draw on veins with red gel food coloring.