Winning with GF Flour

I tried my hand at using gluten free flour with a recipe meant for gluten - and it worked just fine. We had friends coming for dinner and one of the members is gluten free. These cookies looked like a winner with my family - peanut butter and Reese's Pieces. And while I couldn't find peanut butter chips at Aldi - chocolate chips were a fantastic sub. These were a hit with all! Kids and adults. GF peeps and Gluten lovers alike. It was a good experiment for me in using GF Flour - I've tried a few times to make things GF and have had mixed success. I had read that using 1 to 1 flour worked well with cookies - and here's the winning results.

Reese’s Pieces Peanut Butter Cookies
1 cup (2 sticks) unsalted butter, room temperature
1½ cups light brown sugar, packed
½ cup creamy peanut butter
2 large eggs, room temperature
1 teaspoon vanilla extract
3 cups all-purpose flour
1 teaspoon cornstarch
1 teaspoon baking soda
½ teaspoon kosher salt
1 cup peanut butter chips
2 cups Reese's pieces

Line 2 large baking sheets with parchment paper. Set aside.
To the bowl of a stand mixer* fitted with the paddle attachment, add the butter, brown sugar, and peanut butter. Beat on medium-high speed until light and creamy (about 3-5 minutes).
Add the vanilla extract. Mix to combine.
Add the eggs one at a time, mixing well between each addition.
In a separate bowl, whisk together the flour, baking soda, cornstarch, and salt. Add the dry ingredients to the wet ingredients. Mix on low until just combined.
Fold in the peanut butter chips and Reese's pieces.
Chill the dough in the refrigerator for 15 minutes. Near the end of the chill time, preheat the oven to 400°F.
Using a ¼ cup cookie scoop or measuring cup, scoop the dough out onto the prepared baking sheets, about 3 inches apart. Using your hands or the bottom of a glass, slightly flatten each ball of dough. (These cookies don't spread.)
Bake for 8-10 minutes, or until the edges are set and the tops are golden brown. The center of these cookies will be gooey, but they will continue to bake out of the oven.
Allow the cookies to cool on the baking sheet for at least 30 minutes before serving.