In a medium size saucepan over medium heat, heat the shelled walnuts to toast them. Keep them moving with a spatula until they start to lightly brown and smell fragrant. Allow to cool until you can touch them (about 10 minutes), then coarsely chop.

Remove ¼ cup (22g) of the toasted chopped walnuts to use in the recipe. I like to reserve the rest for pressing into the tops of the hot cookies1 when they come out of the oven.

Preheat the oven to 350ºF (177ºC). Line a large baking sheet with parchment paper or a silicone baking mat and set aside.

In a medium size bowl, whisk together the flour, baking soda, cinnamon, and salt. Set aside.

In a large bowl with a hand mixer, or a stand mixer fitted with the paddle attachment, cream together the butter and both sugars until light and fluffy, about 2-3 minutes. Add the egg and beat on high until combined. Add the vanilla extract and molasses and beat on high again until completely combined, scraping down the sides and bottom of the bowl as needed.

Reduce the mixer speed to low, then slowly add the dry ingredients to the wet ingredients and beat until combined. With the mixer still on low, add the oats, chocolate chips, and reserved ¼ cup of toasted walnuts and continue mixing until everything is evenly dispersed. Allow dough to rest for 10 minutes.

Using a cookie scoop (I use this #50 cookie scoop for all of my standard size cookies), drop scoops of dough onto the baking sheet. Bake cookies for 10-12 minutes2 or until edges are just set. Remove from oven and allow to rest on baking sheet for at least 10 minutes. Cookies will look underdone, and will "set" as they cool on baking sheets. Store cookies covered tightly at room temperature up to 5 days. Baked cookies freeze well, as does unbaked rolled dough (up to 2 months). Do not thaw and add an extra minute to baking time.