In a medium mixing bowl, whisk together the all-purpose flour, baking powder, and salt.

In a stand mixer fitted with the paddle attachment, cream together the butter and granulated sugar. Add the eggs in, one at a time, and mix on low until they’re fully incorporated. Add in the vanilla extract and mix on low to combine.

Add the flour in a little bit at a time, and stir on low to mix. Once the flour is fully mixed in, divide the dough in half and put half to the side. Add red gel dye to the remaining dough, a drop or two at a time, and mix. Continue adding dye until you get the color you want.

Form both the untinted dough and the tinted dough into separate rectangles and wrap each in plastic wrap. Refrigerate for 15 minutes.

Roll each piece of dough out to a 9” x 16” rectangle. I prefer to do this between two pieces of wax paper. Refrigerate the dough for 30 minutes.

Remove one piece of wax paper from each rectangle and place the pieces of dough together. Go over the dough with a rolling pin so that the two pieces bind together. Refrigerate for 30 minutes.

Trim the edges so that the colors match up evenly. Roll the dough into a log starting with a long side and with the red side down (so that the red is on the outside of the log). It’s important to really pinch the first rotation together because it’s easy to end up with gaps at the center of the log. Remove the wax paper as you go and squeeze the log firmly but gently as you roll to make the cookies seamless. Wrap the cookie dough log in plastic wrap, and then place the wrapped cookie dough inside the cardboard center of a roll of paper towels that’s been cut lengthwise. This helps the cookies hold their round shape and not flatten too much on the bottom. Refrigerate for 2 hours.

Roll the cookie dough log to make sure it’s evenly round with no flat edges, then unwrap the plastic wrap. Cut off the end pieces that look like they’ll be too small or won’t have enough of a spiral. Pour the decorating sugar and the sprinkles onto a rimmed baking sheet, and mix them together. Roll the log through the sprinkles and sugar, making sure to press the sprinkles into any spots that might get missed. Freeze the dough for 1 hour.

15 minutes before you pull the dough out of the freezer, preheat the oven to 350 F (176 C).

Cut the cookie dough into ¼” slices. Place the sliced dough onto a parchment paper lined baking sheet 2” apart (these cookies will spread). Bake for 10 minutes. Allow to cool for 2 minutes before removing them to a wire rack to cool completely.