In the bowl of a stand mixer fitted with the paddle attachment, combine the butter, confectioners' sugar and salt. Mix on medium speed until everything is well-combined and creamy but not aerated, 1 to 2 minutes. Add the water and/or extracts and continue mixing on medium until thoroughly combined, 3 to 4 minutes.

Add the flour to the butter mixture and mix on low, scraping down the sides and bottom of the bowl occasionally. Mix until no dry pockets remain, 2 to 3 minutes.

Lay an 13-by-18-inch (33-by-45-centimeter) piece of parchment paper on your countertop, with one of the long sides facing you.

Remove about 1 ⅓ cups (300 grams, or a little less than half) of the dough from the bowl and place it on one side (left or right) of the parchment paper. Fold the parchment paper in half like a book, covering the dough. Press the dough down gently to flatten it a little. Using a rolling pin, roll the dough out between the two halves of the parchment sheet until it is spread edge-to-edge within the parchment paper.

It's time to color your dough. You'll need four colors, and you have options: gel food coloring, liquid food coloring and natural colored powders.

Divide the remaining dough into 4 portions. Color each portion individually with the instructions below.

If using gel color, place one dough portion in a small bowl. Add a drop of gel food coloring and stir well to blend the color into the dough.

If using liquid color, place one dough portion in a small bowl. Add a drop of liquid food coloring and stir well to blend the color into the dough.

If using colored powders, place one dough portion in a small bowl. Add a small amount of your colored powder to start with — ½ teaspoon at a time is recommended.

Peel the parchment paper off the top of the uncolored dough sheet, but leave the dough on the bottom parchment.

Take one color of dough and shape it into a tube 9 inches (23 centimeters) long. Place the dough onto the bottom edge of the plain dough sheet.

Lifting up the bottom edge of the parchment sheet, begin rolling the plain dough sheet around the colored dough log.

Repeat the coloring, rolling and cutting steps with the remaining dough colors.

Place two of the dough logs next to each other and place the other two on top of them, so you have a two-by-two formation.

Using a sharp knife, cut the dough log in half. Take the two halves and stack them on top of each other.

Repeat the rolling, cutting and stacking steps two to three more times.

Roll the final log out to a length of approximately 14 inches. Wrap the dough log in parchment paper.

Position racks in the upper and lower thirds of the oven and preheat to 350 degrees. Line two large sheet pans with parchment paper.

To make shortbread slice-and-bakes: Remove the chilled dough from the refrigerator. Place your exterior decoration in a separate sheet pan or baking dish. Lightly brush the exterior of the dough log with water. Roll the dough around in your decoration.

Cut the log into approximately ¼-inch (⅔-centimeter) thick slices. Place the cookies on the lined pans.

To make shortbread cutouts, lay a piece of parchment paper out on your counter. Cut the dough log into approximately ¼-inch (⅔-centimeter) thick slices.

To bake the slices or cutouts: Bake the cookies for 15 minutes, or until the tops are matte and pale but the cookies have not yet started to brown.