Preheat the oven to 300 degrees F. Line 3 cookie sheets with parchment paper.
Cream butter, sugar and brown sugar in the bowl of a stand mixer on medium speed for about 2 minutes. Add eggs, vanilla and lemon juice, blending with mixer on low speed for 30 seconds, then medium speed for about 2 minutes, or until light and fluffy, scraping down bowl.
With mixer on low speed, add flour, oats, baking soda, salt and cinnamon, blending for about 45 seconds. Don’t overmix. Remove bowl from mixer and stir in chocolate chips and walnuts.
Portion dough with a scoop (about 3 tablespoons)* onto a baking sheet lined with parchment paper about 2 inches apart. Use the palm of your hand to flatten the domes of the cookie dough balls to mimic the same shape as the DoubleTree Chocolate Chip Cookies. Bake for 20 to 23 minutes, or until edges are golden brown and center is still soft.
You can freeze the unbaked cookies, and there’s no need to thaw. Preheat oven to 300°F and place frozen cookies on parchment paper-lined baking sheet about 2 inches apart. Bake until edges are golden brown and center is still soft.
Notes
*If you're using a cookie scoop, we recommend using a heaping #24 cookie scoop for cookie dough balls that are three tablespoons. We prefer a bigger cookie, closer to 4 tablespoons (#16 cookie scoop) for a bigger cookie that more closely replicates that DoubleTree Chocolate Chip Cookies.