Ensure you have enough time and space to make these cookies, as the dough requires chilling, cookies need cooling, and icing takes up to 24 hours to set.

Whisk together flour, baking powder, and salt in a medium bowl, then set it aside.

In a large bowl, use a mixer to beat softened butter and granulated sugar until smooth and creamy, about 3 minutes. Add the egg, vanilla, and optional almond extract, then beat for about 1 minute until combined, scraping down the bowl as needed.

Add the dry ingredients to the wet and mix on low speed until just combined; if the dough is too soft, add 1 more Tablespoon of flour.

Divide the dough into two equal parts, place each on lightly floured parchment or a silicone mat, and roll to an even 1/4-inch thickness, adding more flour if necessary.

Lightly dust one rolled dough with flour, cover with parchment, then layer the second rolled dough on top. Cover and refrigerate for at least 1–2 hours or up to 2 days.

Preheat oven to 350°F (177°C) and line baking sheets. Remove chilled dough, cut into shapes with a cookie cutter, then re-roll the remaining dough scraps and continue cutting. Repeat with the second piece of dough.

Arrange cookies about 3 inches apart on baking sheets and bake for 11–12 minutes, or until the edges are lightly browned. Let cookies cool on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely before decorating.

Using a fork, stir confectioners’ sugar, vanilla, corn syrup, 4.5 Tablespoons of water, and optional salt in a medium bowl until very thick. Switch to a whisk and add an additional 1/2 Tablespoon of water at a time until the icing forms a ribbon that holds shape for a few seconds before melting back into itself.

If tinting the icing, stir in gel food coloring starting with 1–2 drops, adding more as needed to reach the desired color, remembering that color darkens as it dries.

Decorate cookies as desired by dipping them into the icing, or using squeeze bottles or piping bags with tips (e.g., Wilton #4) to outline and fill. If adding sprinkles, do so immediately after applying icing.

You can enjoy cookies before the icing completely dries, which typically takes 24 hours; no need to cover them during this time. Store decorated cookies covered for up to 5 days at room temperature or up to 10 days in the refrigerator.