In a large bowl, using an electric mixer, beat ½ cup unsalted butter½ cup unsalted peanut butter½ cup granulated sugar, and ½ cup light or dark brown sugar together until fluffy, about 3 minutes. Scrape down the bowl and beat in 1 large egg, 1 large egg yolk, and 1 teaspoon pure vanilla extract until combined. In a medium bowl, whisk together the 1 ½ cups oat flour, ¾ teaspoon baking soda, and 1 teaspoon fine sea salt. Beat the dry mix into the butter sugar mixture until combined. Stir in the 1-1½ cups semisweet chocolate chips.
If at all possible, refrigerate the dough in an airtight container for 12 hours and up to 2 days. If you don’t have enough time, try to get at least 30 minutes.
When ready to bake, preheat the oven to 325℉. Line 2 baking sheets with parchment paper. Remove the chilled dough from the fridge and scoop balls of dough, about 1-2 teaspoons’ worth. Place on sheets at least 2 inches apart. Bake for about 13-15 minutes, until edges are set and lightly browned. Remove from oven and let cool completely on a rack.
Notes
Chill the dough. Like most cookie doughs, this gluten-free peanut butter chocolate chip cookie dough benefits from some time in the fridge. I try to prep the cookie dough at least a day in advance of baking the cookies. This allows the gluten-free flour to fully hydrate. The cookies' flavor will also be much deeper and more delicious the longer you let the dough rest.
Bang the pan. I love a flatter cookie, so when I remove the pan from the oven, I give it a firm slam down on the counter. This helps the cookies settle and become extra chewy.
What temperature to bake? I like baking the cookies on 325F so that they don't get too puffy. This also helps the cookies to cook evenly without burning. However, I've experimented with baking at 350F, and this also works; you'll just need to bake them for a few minutes less time.
Make refined sugar-free. Use coconut sugar in place of the granulated sugar and brown sugar.
Dairy-free options. Try your favorite non-dairy butter in place of the butter.