In a large bowl, combine powdered sugar, milk, and light corn syrup. Whisk until smooth. If the mixture is too dry, add additional milk, one teaspoon at a time.
Stir in vanilla and almond extracts.
The glaze should be thick, and not run off the cookies, it is too thin add more powdered sugar.
Divide glaze into four small bowls. Prepare 4 toothpicks.
Working with one bowl at a time, use a toothpick to dip it into the food coloring bottle and then into the glaze. To just add a few droplets of food coloring about.
Repeat with the remaining glaze and colors.
Drag the toothpick through the food coloring droplets and glaze until it creates a nice swirl, marble effect.
Dip the surface of each cookie into the marbled glaze, place on a cooling rack, and let the glaze settle. If using sprinkles, add them immediately after dipping the cookies into the glaze.
Keep cookies in an airtight container at room temperature.