In a large bowl whisk together flour, cocoa powder, baking powder, and kosher salt. Set aside.

In another large bowl, melt the butter (I used the microwave) just until melted but not hot. Whisk in the sugar followed by the egg and vanilla. Whisk vigorously until the mixture is emulsified. You shouldn’t see any streaks of butter or egg.

Slowly stir in the flour mixture.

It does look like a dry dough, so I like to finish by hand, squeezing the dough together. This incorporates the flour faster without developing too much gluten.

Roll your dough while it is at room temperature. Divide the dough between two pieces of parchment, shape into a disl, and place another piece of parchment on top of each.

Roll the dough to approximately ¼ inch. You will have the best results if rolled between two pieces of parchment, but you can also roll out on a lightly floured surface.

Refrigerate the dough until chilled. This will only take 30 minutes, but I like to give it a full 2 hours or overnight to let the gluten relax.

When you are ready to bake, preheat your oven to 325° F convection or 350° F conventional, and line two baking sheets with parchment paper.

Unstick the parchment from both sides of the dough, then cut shapes with a lightly floured cookie cutter. Chill the cookies before baking. It will only take about 20 minutes.

Bake in preheated oven for 7-9 minutes or until the cookies look matte in the center and have a few small cracks. I bake all the same shapes on one sheet to ensure even baking.

Cool completely before icing.

In a large bowl add all the powdered sugar and corn syrup. Slowly add the milk, whisking to combine. Add milk slowly so that the icing doesn’t get too thin.

Separate the icing into different bowls and add food dye if desired. Be sure to keep an eye on the consistency and stop adding if it gets too thin. Gel food coloring is best for vibrant colors.

When decorating with this simple powdered sugar icing, I use one consistency for outlining and flooding unlike royal icing where I have two different consistencies. The icing should flow in a thick ribbon off your whisk. It should rest for a moment on the surface of the icing in the bowl before disappearing. If it is too thin, add more powdered sugar.

Transfer to piping bags or clean squeeze bottles.