Allow butter, cream cheese, and egg to reach room temperature.

In a medium bowl, whisk together flour, cornstarch, baking powder, and salt; set aside.

In a large bowl, using a hand-held mixer or stand mixer fitted with a paddle attachment, beat the butter and cream cheese on medium speed until completely smooth and creamy (about 3 minutes).

Add sugar and beat on medium-high speed until light and fluffy, about 2 minutes. Add in the egg, vanilla, and almond extracts and beat on high speed for another minute. Scrape down the sides and bottom of the bowl as needed between additions.

On low speed, gradually incorporate half of the flour mixture into the wet ingredients until just combined; add the remaining flour mixture and mix until just combined. This cookie dough will be soft and creamy!

Generously flour your work surface and rolling pin. Divide the dough into two halves and place each on parchment paper sized for your baking pans. Roll each half to a ¼-inch thickness, re-flouring the rolling pin as needed to prevent sticking. Roll out the dough before chilling; this makes the process easier. Stack the pieces with parchment paper between each layer and refrigerate for at least 2 hours or up to overnight. Chilling the dough is essential to help the cookies maintain their shape during baking.

The next day, preheat the oven to 350°F (175°C). Line 2-3 large baking pans with parchment paper (preferred over silicone baking mats for these cookies).

Remove one chilled cookie dough piece from the refrigerator. The dough may seem hard but is softer than it appears. Cut into shapes with flour-dipped cookie cutters. Place each cookie about 2 inches apart on prepared baking sheets. Re-roll dough scraps and repeat with the remaining dough.

For 3-inch cookies, bake for 11-12 minutes until VERY lightly golden around the edges, rotating the baking sheet halfway through the bake time. If using smaller cutters, bake for 7-10 minutes; larger cutters may require 12-13 minutes. Watch your first batch closely to adjust timing. DO NOT OVERBAKE! Cookies should remain around ¼-inch thick and soft.

Allow cookies to cool on the baking sheet for 5 minutes. Transfer parchment paper with cookies to a cooling rack to cool completely. Once cool, decorate with Bakery Frosting or Easy Royal Icing and sprinkles.

In a stand mixer bowl fitted with a paddle attachment, combine ½ cup room-temperature water and meringue powder. Mix on low to dissolve, about 1-2 minutes.

Add powdered sugar and mix on low. Add corn syrup as the mixture comes together. Increase mixer speed to medium-high and beat for 5 minutes or until stiff peaks form. Avoid overmixing to prevent crumbly icing.

Divide the icing and adjust consistency with additional water for outlining, detailing, and flooding. For flood consistency, icing should drizzle and smooth out within 10-15 seconds. Adjust with more water or sifted confectioners' sugar as needed.

When not using Royal Icing, place a damp paper towel directly on its surface to prevent crusting.

Decorate completely cooled cookies with piping or frosting, adding optional sprinkles or decorating sugar.

This icing sets in about 2 hours at room temperature. To speed up drying or create a sheen, use a fan heater on low, box fan, or oscillating fan, allowing 30-45 minutes between layers. For stenciling, ensure the base coat dries overnight before decorating. Allow cookies to dry overnight before storing with parchment paper between layers for best results.