Add the sugar and butter to a bowl and mix with a mixer until smooth.

Add the vanilla and eggs. Mix well.

Add the flour, baking powder, and salt. Switch to the paddle attachment and mix on low for about 2-3 minutes. The dough should be pulling away from the sides of the bowl.

Split the dough evenly and put it in two different bowls. Add the green coloring to one and the purple coloring to the other. Knead by hand or use the mixer. (if you do use the mixer, be sure to clean the mixer so that the colors don't bleed) Mix until the dough is colored well.

Roll out the dough balls using a rolling pin. They should be about 1/4 inch thick and rectangular-shaped.

Put the green dough on top of the purple dough.

Use a pizza cutter or knife to trim off the edges so that each side is straight and the layers are lined up.

Start at the longer end and roll the dough slowly. Press any crackers or breaks back together.

Roll the log of cookie dough in parchment paper or plastic wrap. Cover the entire log, even the ends, and put it in the fridge for one hour.

Preheat the oven to 325 degrees. Line baking sheets with parchment paper.

Take the log of dough out of the fridge and cut the ends off with a serrated knife.

Continue to cut slices of dough about 3/8 of an inch thick. (These cookies will spread while baking so smaller cuts will be thinner cookies and larger cuts will be thicker cookies)

Put each cookie with the spiral side up on the baking sheet. Leave a bit of space in between each cookie.

Put the sheet in the oven for 12 minutes or until the edges are set and slightly browning on the bottom.

Let the cookies cool on the pan for 5 minutes before removing.