In a medium bowl, whisk together 2 cups of all-purpose flour, 1 teaspoon of baking powder, and a pinch of salt until fully combined and clump-free.

In a large mixing bowl, use a hand mixer to beat together 3/4 cup of softened unsalted butter and 3/4 cup of sugar until light and fluffy.

Add in 1 large egg and 1 teaspoon of vanilla extract to the butter-sugar mixture, blending well until fully combined.

Gradually incorporate the dry ingredient blend into the wet mixture, stirring until a cohesive dough forms. Divide into two halves, wrap each in plastic wrap, and chill for 1 hour.

Preheat your oven to 350°F (180°C) and line baking sheets with parchment paper.

After chilling, roll one half of the dough to about 1/4 inch thick, using skull-shaped cookie cutters to cut out shapes.

Bake the cookies in the preheated oven for 8-10 minutes or until the edges turn golden brown.

In a mixing bowl, whisk together 2 cups of confectioner's sugar with 2 tablespoons of milk or water until smooth.

Once cookies have cooled, apply a base layer of royal icing and pipe designs with gel food coloring.