Tate's Bake Shop Peanut Butter Chocolate Chip Cookies

Last weekend I made another recipe from Kathleen King's (of Tate's Bake Shop) Baking for Friends cookbook. It's not overly complex and produces a cookie that has just the right amount of peanut butter flavor and isn't gritty. They had a nice crispness as well and were great warm out of the oven. 

Ingredients
1 1/2 cups unbleached all-purpose flour
1 teaspoon baking soda
1/4 teaspoon salt
1 cup firmly packed dark brown sugar
4 tablespoons ( 1/2 stick) salted butter, at room temperature
1/4 cup vegetable shortening or coconut oil
1 large egg plus 1 large egg yolk, at room temperature
1/2 teaspoon pure vanilla extract
1 cup smooth peanut butter
1 1/2 cups (9 ounces) chocolate chips

Instructions
Position the oven racks in the top third and center of the oven and preheat the oven to 325 degrees F. Line 2 large rimmed baking sheets with parchment paper or silicone baking mats. 
In a medium bowl, whisk together the flour, baking soda, and salt. In a large bowl, beat the brown sugar, butter, and shortening with an electric mixer set on high speed until combined, about 1 minute. Beat in the egg, followed by the egg yolk and vanilla. Add the peanut butter and mix well. With the mixer on low speed, mix in the flour mixture, just until combined. Mix in the chocolate chips. 
Roll the dough into 30 walnut-sized balls. Arrange about 2 inches apart on the prepared baking sheets. Using a dinner fork, press an X into the top of each cookie, flattening it to about half of its original thickness. Refrigerate the remaining dough balls on a plate while you bake the first batch. 
Bake, rotating the positions of the sheets from top to bottom and front to back halfway through baking, until the cookies are golden.
Yields 3 dozen cookies