1/2 to 1tablespoonmilkany kind of dairy or nondairy milk you like or cream
1tablespoonpure maple syrup
1/4teaspoonpure vanilla extract
Preheat the oven to 350 degrees F. Line two baking sheets with parchment paper or silicone baking mats. Set aside.
In a microwave-safe medium bowl, melt the coconut oil and set aside to cool.
In a large bowl, whisk together the flour, oats, baking soda, pumpkin pie spice, cinnamon, and salt. Set aside.
To the bowl with the coconut oil, add the coconut sugar and stir until well combined. Once combined, whisk in the egg yolk. Add the pumpkin, maple syrup, and vanilla, and whisk until the mixture is well blended. It will be very thick. Make a well in the center of the dry ingredients. Pour the wet ingredients into the well, then stir and fold the batter by hand with a rubber spatula or spoon, just until combined and the flour disappears. The dough will be very thick and will seem dry, but keep stirring and folding and it will come together. Do not overmix.
With a cookie scoop or spoon, portion the dough by 2 tablespoonfuls. Roll into balls and place on the baking sheet, leaving about 1 1/2 inches between each. Lightly flatten the tops of the balls to help the cookies spread in the oven, but do not flatten them completely.
Bake the cookies for 11 to 12 minutes, until very lightly browned on the edges, dry to the touch, and still appearing soft in the centers. Allow the cookies to cool 4 minutes on the baking sheet, then transfer them to a wire rack to cool completely.
While the cookies cool, make the glaze: In a medium bowl, whisk together the powdered sugar, 1/2 tablespoon milk, maple syrup, and vanilla until evenly combined. If the glaze is too thick to drizzle, add additional milk 1/2 teaspoon at a time until you reach your desired consistency.
To frost: Transfer the cookies to a plate or clean sheet of parchment. Dip a fork into the glaze and drizzle it over the top of the cookies in a zigzag patter. Let the cookies sit at room temperature until the glaze sets, about 20 minutes. Enjoy!
The cookies' flavor is best on Day 2. Store leftovers in an airtight container lined with paper towels at room temperature for up to 1 week or freeze for up to 3 months. Thaw overnight in the refrigerator.