2cups(340g)chocolate chips, or a combination of peanut butter and chocolate chips
Preheat the oven to 350 degrees.
In a large bowl combine the butter and peanut butter and beat the mixture until it is light and fluffy (you can do this with a hand mixer or with an electric mixer fitted with the paddle attachment). Add the brown and white sugars and mix until well combined. Add the eggs and mix for 1-2 minutes, until the mixture is well combined and light in color. Add the milk and vanilla and mix. Add the dry ingredients and mix just briefly. While there are still large spots of flour, add the chocolate chips (or peanut butter chips or both) and mix until the flour is completely mixed in and the mixture is well combined. Let the cookie dough sit for 15 minutes before scooping onto the baking sheets. It will firm up as it sits.
When ready to bake, scoop tablespoon-sized balls of dough onto silpat or parchment-lined baking sheets leaving about 1 to 2 inches in between the cookies to allow for spreading as they bake. Bake for 10-11 minutes, taking care not to overbake in the slightest! Leave the cookies on the baking sheet for 2-3 minutes after baking before removing them to a cooling rack. This will help them set up and be firm enough to transfer without having them overbake in the oven. The cookies may look slightly underbaked but they will firm up as they cool. Resist the urge to eat them warm as they taste much better cooled.
I pop baked and cooled cookies into the freezer (in a large tupperware or freezer-safe ziploc bag) and they taste great out of the freezer, especially if they are left to sit at room temperature for a few minutes.