Preheat your oven to 300°F. Then, in a medium bowl, cream together the butter, brown sugar, and granulated sugar. Add eggs, vanilla extract, and lemon juice, and mix until light and fluffy. Slowly add the flour, oats, baking soda, kosher salt, and ground cinnamon, and mix well for another 3-5 minutes. Slowly fold in the chocolate chips and walnuts, and mix well.