Preheat oven to 350 degrees Fahrenheit
Line a baking sheet with parchment paper
Sift dry ingredients in a bowl and set aside
Cream together the butter and sugars for about 3 minutes until smooth, then add the peanut butter and mix until combined
Add egg and vanilla extract and mix until combined, then add dry ingredients and mix until just Incorporated. You don’t want to over mix
Add both chocolates and using a rubber spatula, mix until all Incorporated
Form dough into 12 balls (or 24 if you want them smaller) and place on baking sheet (no more than 6 at a time)
Press down lightly on each ball to flatten it just a tad
Add several chocolate pieces on top of each cookie
Bake for 13 to 15 minutes. Cookies will have rounded out in the oven and spread, forming large cookies
Let cool in pan for about 5 to 7 minutes and then transfer to cooling rack