Mix baking powder and flour. Sift well.
In a mixing bowl cream the unsalted butter, peanut butter and sugar. Beat well. Next add egg and vanilla. Beat well. Mix in the flour mixture. Combine well.
Now cover the dough and refrigerate for one hour or until it is easy to handle.
On a well-floured surface, roll out dough to 1/4-inch thickness. Use a cookie cutter to cut cookies. Place in a greased baking sheet.
Now press a damp fork onto cookies and make deep crisscross patterns. (If you like, you can use a fork dipped in white sugar or flour.)
Bake 8 minutes in a preheated 200C oven.
Serve and enjoy.
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