Cream the butter in a stand mixer or in a bowl using a hand-held electric mixer until smooth.
Completely mix in the sugar. Next, add the egg, baking powder, and vanilla. Mix until creamy.
Lightly whisk the flour and salt in a medium bowl. Slowly mix them into the wet ingredients in the mixer, one cup at a time. It is done once the dough is no longer "sticky" and has a play-dough-like feel. The dough should have pulled away from the sides of the bowl and will be easy to form into a ball.
Split the dough into three equal parts. Color one part yellow, one part orange, and leave one uncolored. *See notes below for best results.* Layer them into a plastic-wrapped line bread pan on one half of the pan(for a single recipe.) The first layer is yellow, then orange, and lastly white. Chill for at least 2 hours in the refrigerator.
Once the dough is chilled, it is time to shape it and preheat the oven. Preheat the oven to 350°F and line cookie baking sheets with parchment paper. Then remove the dough from the bread pan and plastic wrap and cut it into 1/4 inch thick slices. On a cutting board, take one slice and, angling the knife, cut it into a triangle. Continue making triangles all the way across the slice. Then, place the candy corn cookies on the prepared baking sheet. Pat in a sprinkle of sugar for an added touch of fun.
Bake these candy corn sugar cookies for 8-10 minutes. Remove them from the oven and let them sit on the baking sheet for a few minutes before transferring them to a cooling rack.Store candy corn cookies in an airtight container for up to 7 days with a piece of sliced bread(to keep them super soft.) You can freeze candy corn cookies for up to one month.