1) Preheat oven to 350 degrees F2) In the bowl of an electric mixer, add peanut butter and sugar and mix on high speed until fluffy, about 2-3 minutes. Add in vanilla extract and mix until combined.3) Add in flour, oats, salt and baking soda, mixing on medium speed. The dough will look crumbly and you want the peanut butter mix to be broken up into clumps. Add milk with the mixer on low speed, and mix until a dough forms. Fold in chocolate chips.4) Make sure dough is completely combined, and roll it into a ball with your hands. Place it in the middle of an 8×8 baking dish, pressing it to fit. Bake for 18-20 minutes, or until set and golden on top. Let cool completely, then cut into 9 squares.