Directions:

Preheat the oven to 350°F. In a medium bowl, add flour, baking powder & salt (measuring the flour with a scale is the most accurate). Using a whisk, stir to combine and get the lumps out. Set aside.
In a large bowl, add butter and sugar. Beat with an electric mixer for 3 minutes. Add the egg and vanilla and beat another minute. With the mixer on low, gradually add the flour mixture.
Blend until the dough begins to pull away from the sides of the bowl. Take the dough out of the bowl and place on a large piece of parchment paper. Use your hands to knead the dough for a few minutes. Divide the dough into two sections and wrap with parchment paper.
To roll dough, place another piece of parchment paper on top of dough and roll with a rolling pin until the dough is between ?" and ¼" thick. Cut into shapes and remove the excess dough. Don't move the shapes, leave them where they are and place on a cookie sheet. Bake for 10-13 minutes or until slightly golden brown around the edges. Let them cool and decorate with royal icing (or you can freeze them before decorating and keep them for several months). Makes 20 (2-inch) cookies.

Directions:

Place all icing ingredients in a large bowl and beat with an electric mixer on low for 6 minutes. It will be very thick and fluffy. Add 4-5 tablespoons of water and mix to combine. That's your medium consistency (it should be like toothpaste). Divide and color as desired. We used six colors, plus some plain white. Place in piping bags and secure opening with twist tie. Cut the tiny corner and pipe a line around the edge of the cookies. Let set for 30-45 minutes. Then fill in with some thinner icing. You can squeeze a little icing into a bowl and add a few drops of water. Stir until it's soupy. Use a spoon to fill in the middle area of the cookie. Let set another 30-45 minutes. Repeat with desired colors. Then add more decorations on top by piping with various colors. For example, we used plain white to pipe a garland on top of the green Christmas tree. Then added dots of red icing for the ornaments. Or you can add sprinkles while the icing is still wet. Let icing set before serving. Store cookies covered at room temperature for 5-7 days.