Preheat the oven to 375 degrees. Line 2 baking sheets with silicone mats or parchment paper.

In a medium sized mixing bowl, combine the flour, baking soda, baking powder, and salt. Set aside.

In a large bowl or the bowl of an electric mixer, beat together the butter and peanut butter on high speed until light and fluffy, about two minutes.

Add both sugars and beat until smooth. Add the egg and egg yolk, beating well after each addition. Beat in the milk and vanilla extract.

With the mixer on low speed, slowly add the flour mixture to the peanut butter mixture. Once it's mostly combined, turn the mixer up to medium speed and beat until cohesive.

Scoop rounded Tablespoons of dough onto the prepared pans. Use a large serving fork to press a criss cross shape into the top of the dough, pressing into about ? inch thick disks. Sprinkle the dough with granulated sugar.

Bake the cookies for 9-10 minutes, removing them from the oven when the edges are just set, but the centers are still puffy. Allow the cookies to set up on the pan for no more than 2-3 minutes, then remove to a wire rack and cool completely.