Preheat your oven to 350℉
In the bowl of a stand mixer, or a large bowl with a hand mixer, cream the butter until smooth.
Add the peanutbutter and sugars and cream until light and fluffy. 2-3 minutes
Add the egg and vanilla and beat until combined.
Whisk together the flour, baking soda and salt and add to the bowl. Beat on low speed until just incorporated.
Roll the dough into balls weighing 20 grams each or 1” in diameter and roll them in granulated sugar.
Place them on a parchment lined baking sheet spaced about 2” apart.
Bake for 11-12 minutes, or until the tops begin to crack.
Remove from the oven and press a chocolate covered pretzel onto te top of each cookie.
Move the cookies to a rack to cool completely.