With the paddle attachment of a stand mixer cream butter until light and fluffy.

Add in brown sugar and white sugar and continue to mix until well incorporated.

Add in egg and vanilla and continue mixing until well blended.

In a separate bowl whisk together flour, baking powder and salt.

Gradually add flour mixture to butter mixture mixing after each addition until all the flour is incorporated.

Add in any mix ins and mix gently on low.

Lay out a piece of wax paper on a flat surface. Scoop the dough into the center of the wax paper. Use the wax paper to help roll the dough into a long shape with a diameter of about 2 inches.

Wrap the dough in the wax paper and refrigerate for at least 1 hour.

Preheat the oven to 350

Line a baking sheet with parchment paper.

Slice the cookie dough into ¼- ½ inch slices.

Place dough slices on prepared cookie sheet a couple of inches apart.

Bake for 10-14 minutes or until they are a very lightly golden brown around the edge and appear dry in the center.

Allow to cool for 2-3 minutes on the baking sheet before removing and allowing to cool completely on a wire rack.