These iced oatmeal cookies are the perfect mix of crisp and chewy. The slice-and-bake dough can even be frozen, making it possible to enjoy oven-fresh cookies whenever the craving strikes!
In the bowl of a stand mixer fitted with the paddle attachment, or in a large mixing bowl with an electric mixer, cream together the butter and both sugars on medium speed until light and fluffy, about 3-5 minutes. Scrape down the sides and bottom of the bowl with a rubber spatula as needed.
12 tablespoons unsalted butter, 1 cup lightly packed dark brown sugar, ½ cup granulated sugar
Add the eggs and vanilla; mix until well combined.
2 large eggs, 1 teaspoon vanilla extract
In a separate bowl, whisk together the flour, cinnamon, salt, and baking soda. Slowly add to the butter mixture until just combined. Stir in the oats until well distributed.
2 cups all-purpose flour, 1 ½ teaspoons cinnamon, 1 teaspoon fine sea salt, ½ teaspoon baking soda, 2 cups rolled oats
Place a sheet of parchment paper on the countertop. Add half of the cookie dough; use the parchment paper to roll the dough into a log about 1 ½ inches in diameter. Twist the ends of the parchment paper tightly. Repeat with a second piece of parchment and the remaining cookie dough. (If it is easier, feel free to divide the dough into thirds instead of in half to roll the dough logs.) Freeze the cookie dough logs for at least 1 hour or up to 3 months.
When ready to bake, preheat the oven to 350°F. Line baking sheets with parchment paper or silicone baking mats.
Unwrap the cookie dough and cut into slices about ½-inch thick. Place the sliced cookie dough on the prepared baking sheets, leaving about 2 inches between each cookie.
Bake the cookies for 13-14 minutes, or until the edges are deeply golden but the centers still appear soft. Let the cookies cool on the baking sheet for 3-5 minutes before moving them to a wire rack to finish cooling.
In a bowl, whisk together the melted butter, powdered sugar, vanilla, salt, and milk until smooth. If needed, add more milk just a small splash at a time to reach your desired consistency; the icing should be thin enough to dip the cookies into it, but not so thin that it runs off the edges.
Dip the tops of the cookies into the icing, shaking off excess icing. The icing will set in about an hour.
Notes
If you only have light brown sugar, use the same amount as indicated in the recipe and add 1 tablespoon of molasses to the butter and sugar mixture.
The cookie dough logs can be stored in an airtight freezer bag and frozen for up to 3 months. Baked cookies can be stored in an airtight container at room temperature for 3-4 days.