For the sugar cookie: Preheat the oven to 350 degrees F. Line 2 baking sheets with parchment.
In a stand mixer, cream the butter and sugar together well. Add the eggs 1 at a time, mixing between each addition. On low speed, slowly add the flour, baking powder and salt and mix. Add the vanilla extract and 2 teaspoons water and mix just until combined; do not over mix! Refrigerate the dough for 30 minutes
Dust a work surface with flour. Roll out the dough about 1/4 inch thick and cut into shapes using your favorite cookie cutters. Transfer to the prepared baking sheets and bake until no longer translucent and just golden at the edges, 7 to 9 minutes. Cool slightly on the baking sheets, then transfer to a wire rack to cool completely. Continue rolling and baking any remaining dough, re-rolling scraps once.
For the icing: Whisk together the lemon juice, cinnamon, egg whites and orange zest in the bowl of a stand mixer. Using the paddle attachment and on medium speed, gradually add the confectioners' sugar and beat until the icing is the desired stiffness. Transfer the icing to a piping bag and pipe on the cookies in desired decorative patterns.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.