Preheat your oven to 400°F.

Add 1 Cup Butter to the mixing bowl of your stand mixer.

Add the 2 Cups Powdered sugar and mix until fluffy - about 3-5 minutes.

Add the vanilla and egg and mix again until incorporated.

In another medium mixing bowl, add the flour, salt and baking powder. Mix with a whisk and gradually add to the butter mixture while on low speed.

Once the cookie dough has come together, using your hands knead a little in the stand mixer bowl then split in two. Wrap the one half of cookie dough in plastic wrap and set aside.

The other roll out on a lightly floured surface until about ¼" thick. Using a snowflake cookie cutter cut out the shapes and transfer to a cookie sheet lined with parchment paper.

Take the scraps and roll out again, repeating until that first batch has filled up the cookie sheet. The cookies should be 1" apart.

Bake in the oven for abuot 6 minutes, or until the edges start to lightly brown.

While those cookies are baking you can repeat with the second batch on another cookie sheet. Once that first batch comes out, bake this one for 6 minutes again.

Allow the cookies to cool a few minutes then place on a wire rack to cool completely.

Wash the bowl and paddle for your next step.

Add the powdered sugar and meringue powder to the stand mixer bowl. Mix with the paddle a few times to mix up.

Add the vanilla and water, until a good royal icing consistency is reached. It should be almost runny. Enough so that when you lift the paddle up, the icing that falls back into the bowl holds its shape on top for about 5 seconds, before melting into the rest.

Add half of this icing to one piping bag and tie the end.

Add the blue food color to the remaining icing and mix well.

Add this to another piping bag.

Snip the tip so that only a small hole shows, so that the icing can be squeezed out slowly (or use a #1 icing tip).

First pipe the icing around the outside of the cooled cookie. Then flood the inside. Use a toothpick to help move the icing around.

Then take the opposite color and pipe the shape of a star over the top of the other dried icing.

Allow to dry for a few hours before trying to stack on top of each other.