1 1/2 cups unsalted butter
1 1/2 cups white sugar
3/4 cup packed brown sugar
3 cups all-purpose flour
3/4 cup rolled oats
2 1/2 teaspoons vanilla extract
1 teaspoon lemon juice
3/4 teaspoon baking soda
1 teaspoon salt
1/4 teaspoon ground cinnamon
3 cups semisweet chocolate chips
1 1/2 cups chopped walnuts
Cream butter in large bowl. Add both sugars and beat on medium for 2 minutes. Add eggs one at a time, beating well after each addition. Add lemon juice and vanilla; mix well.
In a separate bowl, stir together dry ingredients. Add to creamed mixture and stir well to blend. Add chips and nuts; stir to combine.
Drop by 1/4 cup or 2 ounce scoop on parchment-lined baking pans, 2 to 3 inches apart. Bake at 350 degrees F (175 degrees C) for 13 to 15 minutes or until lightly browned around the edges. Cool; remove from paper and cool completely on wire racks.