Pulse the oats in a food processor 10-12 times until you have a variety of texture—chopped oats with some oat flour. See photo above for a visual.

Whisk the pulsed oats, flour, baking soda, salt, cinnamon, and nutmeg together in a medium bowl. Set aside.

In a large bowl using a hand mixer or a stand mixer fitted with a paddle attachment, beat the butter, brown sugar, and granulated sugar together on medium-high speed until creamed, about 2 minutes. Add the eggs, molasses, and vanilla extract and beat on high speed until combined, about 1 minute. Scrape down the sides and up the bottom of the bowl and beat again as needed to combine.

Add the dry ingredients to the wet ingredients and mix on low until combined. Dough will be thick and sticky. Cover and chill the dough for at least 45 minutes in the refrigerator (and up to 4 days). If chilling for longer than a few hours, allow to sit at room temperature for at least 30 minutes before scooping and baking because the dough will be quite hard.

Preheat oven to 350°F (177°C). Line baking sheets with parchment paper or silicone baking mats. Set aside.

Scoop cookie dough, about 1.5 Tablespoons of dough per cookie, and place 3 inches apart on the baking sheets. Bake for 11-12 minutes or until lightly browned on the sides. The centers will look very soft.

Remove from the oven and allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely before icing.

Place sifted confectioners’ sugar in a medium bowl. Add the vanilla extract and 1 Tablespoon of milk. Use a fork to whisk until combined. It will be impossible to fully combine because this isn’t enough liquid. Add only enough extra milk to make a very very thick icing. I only add about 1 more Tablespoon of milk. Lightly dip the tops of the cookies into the icing. Icing will set after a few hours, so you can stack and gift the cookies.

Cookies stay fresh covered at room temperature for 3 days or in the refrigerator for up to 10 days.