This was already one of our best recipe "finds" on Feast Everyday. It comes from King Arthur Flour and was their cookie of the year for 2015. (To see original recipe, click here.)
But now it is even better because you can make it gluten free by substituting regular flour with a gluten free mix of rice and tapioca flour plus potato starch which is easily pulled together. I also added xanthan gum, which seems to help gluten free baked goods. I also increased the eggs.
I do want to mention, though, that I recommend you use the best chocolate chips you can find, because the dough has 3 cups of chips in it, and the quality of the chocolate chips really affects how good the cookie tastes.
Here is the modified recipe:
Gluten Free Chocolate Chip Oatmeal Cookies
(from King Arthur)
Makes 36 large cookies
2 sticks unsalted butter at room temperature
1 cup light brown sugar, packed
1/2 cup granulated sugar
2 large eggs, at room temperature
1 tablespoon pure vanilla extract
2 cups gluten free mix flour (see below)
1 cup rolled oats
1 teaspoon baking powder
1 teaspoon baking soda
2 teaspoons xanthan gum
1/2 teaspoon salt
3 cups (18 ounces) semi-sweet chocolate chips
5 1/2 - 6 cups (24 ounces) brown rice flour
2 cups (10 3/4 ounces) potato starch
1 cup (4 ounces) tapioca flour
Use the whole bag of brown rice flour, than add 2 cups of potato starch (which may be the entire box) and 1 cup of tapioca flour. Whisk it all together very well, then store in an air-tight container. Fluff the mixture before measuring it out in recipes.
Preheat the oven to 325 degrees F. Lightly grease several baking sheets, or line them with parchment paper. (I recommend parchment paper.)
In a stand mixer using the wire whisk attachment, beat the butter and sugars until smooth. Add the egg, egg yolk and vanilla one at a time, beating well after each addition. Beat until light and airy and fluffy.
Whisk in a separate bowl whisk together the dry ingredients except the chocolate chips - the flour, oats, baking powder, baking soda, xanthan gum and salt.
Change the attachment on the stand mixer to the paddle, or just use a large spatula and do this step by hand. Add the dry ingredients to the butter mixture. Mix until everything is thoroughly incorporated. Be sure to scrape down the sides of the bowl.
Now stir in the chocolate chips so that they are pretty evenly distributed in the cookie batter.
Scoop the dough onto the prepared baking sheets leaving an 1 1/2" to 2" in between. 12 scoops per baking sheet. Slightly flatten each cookie by pressing it down on the top.
Once baked, remove from the oven and let cool on the baking sheet for about 5 minutes. Then transfer once the cookies have set to a cooling rack.
These are really good and worth making.