2cupsextra-thick rolled oatssuch as Bob's Red Mill
kosher or flaky sea saltsuch as Maldon
Instructions
Add walnuts to the bowl of a food processor and process until very fine - on their way to butter. Set aside.
Sift dry ingredients (flour, baking soda, and salt) into a medium bowl. Set aside.
Add butter and both sugars to the bowl of a stand mixer fitted with the paddle attachment. Beat at low speed until combined; increase speed and beat until fluffy, 2 to 3 minutes more. Add walnuts and peanut butter; mix until combined. Add eggs and vanilla; mix until combined. Add flour mixture - cover mixer with a kitchen towel to protect your counters from a flour flurry. Start at low speed until combined, then increase to high for about 1 minute more. Add oats and mix until combined.
Line a baking sheet with parchment paper. Scoop dough into about two tablespoon balls - line them up very close together on the pan (you won't be baking them this way). Once you've scooped all of the dough, lightly sprinkle with kosher or flaky sea salt; cover with plastic wrap. If you plan to bake the cookies the day you make the dough, chill the dough balls in the freezer for at least 30 minutes or the refrigerator for at least 2 hours. If you plan to cook them at a later date, put the pan in the freezer for several hours or overnight. Once frozen, put the dough balls in a gallon size freezer bag labeled with cooking instructions and store them in the freezer.
When you're ready to bake the cookies, preheat the oven to 375°F.
Line a cookie sheet with parchment paper. Arrange the cookies spaced 1" apart on the prepared baking sheet. (Bake just a few or a whole pan full.) Bake cookies until lightly golden and still a bit soft - 10 minutes; 11 or 12 minutes if they start out frozen. Transfer to cooling racks - enjoy warm or at room temperature.
Video
Notes
Note that I use this scoop - which is a 2-tablespoon scoop. If you use a smaller or larger scoop, you'll need to adjust the cooking time accordingly.
If you don't have a stand mixer, use a large bowl and a standard electric mixer / hand mixer to combine the wet ingredients and flour mixture (be sure to use room temperature butter). Then stir in the oats with a wooden spoon or spatula at the end.
Store cookies in an airtight container at room temperature for up to 3 days.