4 ½ cups gluten free old fashioned oats, divided 2 tablespoons cornstarch 1 ½ teaspoons ground cinnamon 1 teaspoon gluten-free baking powder ½ teaspoon fine salt 2 sticks unsalted butter, room temperature ¾ cups granulated sugar ½ cup packed light-brown sugar 2 large eggs 2 teaspoons pure vanilla extract ¾ cup chocolate chips ¾ cup raisins
1. Preheat oven to 350˚. In a blender, process 1 ½ cups oats into a fine meal. Whisk together ground oats, cornstarch, cinnamon, baking powder and salt.
2. In a large bowl, using a mixer, beat butter and sugars until light and fluffy. Beat in eggs and vanilla. With mixer on low, gradually add oat mixture, beating until combined. Fold in chocolate chips, raisins, and remaining 3 cups oats.
3. In batches, drop dough in 2-tablespoonful mounds onto a parchment-lined baking sheet, 2 inches apart. Bake until cookies are golden brown at edges, 15 to 18 minutes. Let cool on sheet on a wire rack 2 minutes, then transfer to rack and let cool completely.