|All purpose flour||1 3⁄4 Cup (28 tbs)|
|Cocoa powder||3⁄4 Cup (12 tbs)|
|Baking soda||1⁄2 Teaspoon|
|Unsalted butter||1⁄2 Cup (8 tbs), softened (1 stick)|
|Sugar||1 Cup (16 tbs)|
|Milk||1⁄2 Cup (8 tbs)|
|Pure vanilla extract||1 Teaspoon|
|Marshmallows||12 Large, cut in half horizontally|
1. Preheat oven to 375°. In a medium bowl, whisk together flour, cocoa powder, baking soda, and salt; set aside.
2. In the bowl of an electric mixer fitted with the paddle attachment, cream together butter and sugar until light and fluffy, about 2 minutes. Add egg, milk, and vanilla, and beat until well combined. Add reserved flour mixture; mix on low speed until combined.
3. Using a tablespoon or 1 3/4-inch ice cream scoop, drop dough onto ungreased baking sheets, about 2 inches apart. Bake until cookies begin to spread and become firm, 10 to 12 minutes.
4. Remove baking sheets from oven, and place a marshmallow, cut-side down, in the center of each cookie, pressing down slightly. Return to oven, and continue baking until marshmallows begins to melt, 2 to 2 1/2 minutes. Transfer cookies to a wire rack to cool completely before frosting.
5. Spread about 1 tablespoon of frosting over each marshmallow, starting in the center and continuing outward until marshmallow is covered.