Add the dry ingredients into the butter mixture, one-third at a time. Mix well in between each addition until all the flour is combined.
Add Color
Take the cookie dough out of the mixing bowl and divide it in half.
To one half, add 1/4 teaspoon of orange gel food coloring. Knead until the piece is orange.
gel food coloring - orange and black
To the other half, add 1/4 teaspoon of black gel food coloring. Mix until well combined, and it is dark black.
Put the black dough on a piece of parchment paper and roll it out into a rectangle, about 9 x 15 inches in size. Take another piece of parchment paper and roll the orange dough into a 9 x 15-inch rectangle.
Keep the pieces on the parchment paper and place both orange and black dough in the refrigerator for 15-20 minutes. Don't combine the two yet! You can stack them but keep parchment paper between the layers.
Make a Dough Log
Take the dough out and place the black rectangle on a cutting board. Lay the orange rectangle on top of the black one, this time with parchment paper facing up, so the two are layered. Carefully peel the parchment paper off the orange layer.
Trim the edges to make them even and form a rectangle. Use a sharp knife or a pizza cutter.
Roll up the dough, starting at the short edge. Use the parchment paper to help you roll and exert gentle pressure as you go.
Wrap the roll of dough in plastic wrap or parchment paper. Refrigerate it for 2 hours before baking the cookies.
Bake the Cookies
Preheat the oven to 350 degrees F. Line the baking sheets with parchment paper or a silicone baking mat.
Take the dough out of the refrigerator, unwrap it and place it on a cutting board.
Slice the dough into 1/4 inch slices and place them on the prepared baking sheet. Use a sharp knife and rotate the dough log if it starts to get squished.
Bake for 10 minutes. Take the cookie sheets out of the oven and let the cookies cool on the sheets for 1-2 minutes. Then place them on a wire rack to finish cooling.
Notes
If you don't have black food coloring use dark purple. Or use yellow for candy corn pinwheel cookies.
Pinwheel cookies are forgiving, so don't be concerned if your rectangles aren't quite square or your cookies are more oval than round. These cookies will expand as they bake, and you will end up with nice-looking cookies.
Use gel food coloring for vibrant festive color.
Don't be tempted to rush the chilling process.
Sprinkle sparkling sugar on top or roll the edges in sprinkles for extra sparkle.
Add 1 teaspoon of pumpkin spice to the flour mixture for a seasonal flavor variation.