Preheat the oven to 400°F. Line a large baking sheet with parchment paper.
Sift all the dry ingredients into a large bowl. Add orange zest, melted coconut oil, and water. Knead just until the dough forms.
Place the dough on a floured work surface. Roll out the dough to ½-inch thick, flouring as needed. Cut out the shapes you like (you can get creative and use any cookie cutters and stamps you have). You should get around 15 cookies, 2 inches each.
Place cookies on the baking sheet, spacing 1 inch apart. Bake for 10 minutes or until golden-brown on the edges. Remove from the oven and cool on a wire rack.
For the icing, sift the powdered sugar into a bowl. Gradually stir in water until the mixture is the consistency of thick cream. If you want to make it more colorful, you can mix in 1-2 drops of any coloring of your choice. Use the icing immediately, as it might dry out. To pipe the icing onto the cookies, use an icing bag with the smallest tip.