Soft. Simple. Sweet.

For the cookie:

• 1 cup old fashioned oats
• 1 cup all-purpose flour
• 1 1/2 tsp. baking powder
• 1/4 tsp. baking soda
• 1/4 tsp. salt
• 1/2 tsp. cinnamon
• 1/4 tsp. nutmeg
• 1 stick unsalted butter
• 1/2 cup brown sugar
• 1/4 cup sugar
• 1 egg
• 1 tsp. vanilla extract

For the icing:

• 1 1/4 cups powdered sugar
• 2 tbsp. milk, plus more as needed
• 1/2 tsp. vanilla extract

Preheat the oven to 350 degrees. Line large cookie sheet with parchment paper. Pulse oats approximately 10 times and then combine remaining dry ingredients and whisk together. Cream together butter and sugars, beating until light and fluffy, about 2 minutes. Blend in egg and vanilla. Mix dry ingredients into creamed mixture until just incorporated. Using a 2 inch (or smaller, if desired) cookie scoop place balls about 2 inches apart. Bake for 10 minutes. Allow to cool on sheet for a minute or two before transferring to cooling rack.

To make icing, combine powdered sugar, milk, and vanilla. Whisk to blend until smooth, adjusting milk or sugar to get a thick glaze. Holding cookies by the side, carefully dip each top of the cookie into glaze and return to cooling rack.

Source: http://www.annies-eats.com/2014/09/04/iced-oatmeal-cookies/