These beautiful cookies are perfect for celebrating Independence Day, as they are a decoration themselves! Using gel food coloring is important, as they have much more vibrant colors.
Make sugar cookie dough, then roll out to ¼-inch thickness. Cut stars out of the dough and transfer to an ungreased baking sheet. Bake for 10 to 12 minutes, until cookies are set and just starting to get golden brown.
In a large bowl, whisk together the powdered sugar, milk, corn syrup, and vanilla until very smooth.
Transfer about 1/3 cup icing to a small, wide bowl or ramekin (wide enough for your cookie to fit in). Dip a toothpick in the blue gel food coloring and then pierce the surface of the icing, making 4 to 5 dots. Use a different toothpick and repeat with red gel food coloring. Use a toothpick to swirl the icings until they are swirled but still separate colors (if you swirl too much it will turn purple).
Dip the tops of the cookies into the icing, twisting as you lift and letting the excess drip off one side.
Transfer to a cooling rack for icing to set. Immediately sprinkle with silver star sprinkles. Repeat with the same bowl until the colors become too muddled, then make a new small bowl of marbled icing and repeat. Let cookies sit until icing has hardened before stacking and storing.

Patriotic Marbled Cookies
Makes 40

Cookies:
1 cup unsalted butter, room temperature
¾ cup sugar
1 egg yolk
1 teaspoon vanilla
2 ¼ cups flour
½ teaspoon kosher salt

Icing:
3 cups powdered sugar
¼ cup milk
3 tablespoons light corn syrup
½ teaspoon vanilla
Red gel food coloring
Blue gel food coloring
Silver star sprinkles

In the bowl of an electric mixer, cream butter and sugar until light and fluffy. Add egg yolk and vanilla; beat until combined. Add flour and salt; mix just until combined. Transfer dough to a large piece of plastic wrap. Flatten dough into a 1-inch high disc, then wrap in plastic wrap and refrigerate for 20 minutes.

Preheat oven to 350°F.

Unwrap dough and place on a lightly floured surface. Use a rolling pin to roll out to ¼-inch thickness. Use a star cookie cutter to cut out cookies, rerolling scraps to cut out more cookies. Place stars on ungreased baking sheets.

Bake for 10 to 12 minutes, until cookies are set and just starting to get golden brown. Let cookies cool for 5 minutes on the baking sheet, then transfer to a cooling rack to cool completely.

In a large bowl, whisk together the powdered sugar, milk, corn syrup, and vanilla until very smooth. Transfer about 1/3 cup icing to a small, wide bowl or ramekin (wide enough for your cookie to fit in). Dip a toothpick in the blue gel food coloring and then pierce the surface of the icing, making 4 to 5 dots. Use a different toothpick and repeat with red gel food coloring. Use a toothpick to swirl the icings until they are swirled but still separate colors (if you swirl too much it will turn purple).

Dip the tops of the cookies into the icing, twisting as you lift and letting the excess drip off one side. Transfer to a cooling rack for icing to set. Immediately sprinkle with silver star sprinkles. Repeat with the same bowl until the colors become too muddled, then make a new small bowl of marbled icing and repeat. Let cookies sit until icing has hardened before stacking and storing.