Mix together the confectioner's sugar and butter until smooth.
Add the egg and vanilla extract and continue mixing. Once everything is combined the mixture may still be a bit lumpy and that fine.
In a separate bowl, mix together the flour, baking powder, and salt.
Add the flour mixture to the butter mixture, about a 1/2 cup at a time, while mixing.* The dough is a good consistency when majority of the dough sticks to the flat beater and not the sides of the bowl. The dough also should not stick to your fingers.
Place a sheet of parchment paper on your workspace and lightly dust with flour. Then roll out the dough on the parchment paper. Lightly flour the rolling pin if dough starts to stick.
Use cookie cutters of your choice to cut out cookie shapes
Place a clean sheet of parchment paper on the cookie sheet and transfer cookie cutouts to the cookie sheet.
Place cookie sheet on middle rack and bake for 7 minutes.
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