Preheat oven to 300 degrees F and place two oven racks spaced evenly.

Cream butter and both sugars in a stand mixer with a paddle for two minutes.

Add eggs, vanilla and lemon juice and blend on low for 30 seconds then on medium for two minutes, scraping bowl half way through.

In a bowl, mix flour, oats, baking soda, baking powder, salt and cinnamon.

With mixer running on low, slowly add the dry ingredients and blend for 45 seconds but do not over mix.

Remove the bowl from the mixer and add in the chocolate chips and walnuts by hand. You will need a wooden spoon or sturdy rubber spatula. (I found it easiest to use my hand to work the chips and nuts into the dough).

Line two rimless cookie sheets with parchment and using a slightly heaping one-ounce scoop, scoop out 12 cookies per pan spaced evenly.

Bake both pans for 10 minutes, rotate pans and bake for 10-13 minutes more. Our cookies took exactly 23 minutes total to bake.

Remove from oven and slide each parchment onto a rack to cool.

Place two new pieces of parchment onto the cookie sheets.

Portion out the rest of the dough and bake the next two pans the same way.

Eat warm or cool and store in an air tight container.