Add the Peanut Butter and the Butter to the bowl of an electric stand mixer and combine for 30 seconds.
Pour in about half of the 1 Cup of Flour, all the Brown Sugar, half of the Milk, the Egg, Baking Powder, Baking Soda, and the Salt. Mix until combined, scraping the sides of the bowl on occasion.
Add in the rest of the Flour and the Milk. Beat until JUST combined and then STOP. Do NOT keep beating this to death.
Stir in the Chocolate Chips by hand. It is so easy to go from "not combined" to "mixed within an inch of its life" when you use a stand mixer.
Pour the batter into the greased pan and spread it around the best you can. Top with the, uh, topping.
Bake 375* for 25-30 minutes or until a toothpick near the center comes out clean.
Cool on a wire cooling rack for 15 minutes to set. Serve warm.