Make the Cookies:

1. Prepare the dough:
   • In a large bowl, beat softened butter and sugar together until light and fluffy (about 2 minutes).
   • Mix in the egg, vanilla extract, and almond extract, if using.
   • In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the wet ingredients and mix until a soft dough forms.
2. Chill the dough:
   • Divide the dough into two discs, wrap in plastic wrap, and refrigerate for at least 1 hour (or up to 2 days).
3. Cut out cookies:
   • Preheat your oven to 350°F (175°C). Line baking sheets with parchment paper.
   • Roll out the chilled dough on a floured surface to about 1/4-inch thickness.
   • Use festive cookie cutters (like stars, trees, or snowflakes) to cut out shapes, and transfer them to the prepared baking sheets.
4. Bake:
   • Bake for 8-10 minutes, or until the edges are just starting to turn golden.
   • Let the cookies cool on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely before decorating.

Make the Royal Icing:

5. Prepare the icing:
   • In a medium bowl, whisk together the powdered sugar and meringue powder.
   • Add water, one tablespoon at a time, until the icing reaches your desired consistency (thicker for outlining, thinner for flooding).
   • Divide the icing into small bowls and tint with food coloring, if desired.
6. Decorate the cookies:
   • Use piping bags or squeeze bottles to decorate the cookies. Add sprinkles or edible glitter while the icing is wet.
   • Allow the icing to dry completely (about 4-6 hours) before stacking or storing the cookies.