Preheat your oven to 375°F. In a large bowl, mix 2 1/4 cups of Make Ahead Peanut Butter Cookie Mix with 1/2 cup of softened butter and 1 teaspoon of vanilla extract. You can do this in a stand mixer or with an electric hand mixer, but it is easy to do by hand with a wooden spoon. If you mix this by hand, it will take approximately 4 minutes to combine. Once the butter and extract are well combined with the mix, add 1 large egg and mix well again until fully incorporated, which will take about 2 minutes. Next, add 1/2 cup peanut butter (smooth or chunky) to the mixture and mix well until the peanut butter is thoroughly incorporated with the mixture, which takes about 2 minutes. (If you prefer, you can substitute with another "nut" butter such as almond butter.) Using a tablespoon, scoop the rounded cookie mixture on to a parchment-lined baking sheet, placing the scooped amounts three inches apart. Using the tines of a fork, slightly flatten each round of cookie dough with a hash mark. (If the tines of the fork stick to the dough, you can dust the tines in flour.) Bake in a 350°F oven (See RECIPE NOTES below) for approximately 8-10 minutes until the edges are golden brown. Remove from the oven, allow the cookies to cool slightly on the baking sheet, and then transfer to a cooling rack to cool completely.