Start by grabbing a large mixing bowl. Beat the softened butter and granulated sugar together until the mixture becomes light and fluffy. This usually takes about 2–3 minutes with a hand mixer.
Next, add the egg yolk and mix until everything is smooth and well combined.
In a separate bowl, whisk together the flour and salt. This step helps distribute the salt evenly throughout the dough.
Slowly add the dry ingredients into the butter mixture. Mix just until a soft dough forms. At this point the dough should be smooth, soft, and easy to handle.
Divide the dough into two equal portions. Place one half in a bowl and add red gel food coloring. Mix until the color is fully blended and vibrant. Place the other half in a second bowl and tint it blue.Gel food coloring works beautifully here because it creates bold color without making the dough sticky. Once both dough colors are ready, it’s time to shape the cookies. Scoop about 1 tablespoon of dough and roll it into a ball using your hands.
Roll each dough ball generously in powdered sugar until it’s completely coated.
Then gently flatten the ball into a thick little disc. Think of it like a small puck shape.
Place the shaped cookies on a tray. Repeat until all the dough is used.
Place the tray of cookie discs into the freezer for at least 1 hour, or until the dough is completely solid. Freezing helps: Create deep crinkles, prevent spreading, keep the colors vibrant.
When you’re ready to bake, preheat your oven to 350°F (180°C).
Line a baking sheet with parchment paper. Place the frozen cookie discs onto the baking sheet, leaving a little space between them.
Bake for 12–15 minutes. You’ll notice the cookies start to puff slightly, and the powdered sugar coating will crack open to reveal the bright red and blue dough underneath.
If the powdered sugar begins to brown, remove the cookies right away. Let them cool completely on the baking tray.
