Oatmeal Cream Pies with Chocolate

Ingredients (18)

• + ¾ cup butter, softened add to pantry
• + ¾ cup light brown sugar add to pantry
• + ½ cup white sugar add to pantry
• ✓ 1 egg
• ✓ 1 tablespoon whole milk
• + 1 teaspoon vanilla extract add to pantry
• + 1 ½ cups quick-cooking oats add to pantry
• ✓ ¾ cup all-purpose flour
• + 2 tablespoons cocoa powder, sifted add to pantry
• + 1 teaspoon ground cinnamon add to pantry
• + ½ teaspoon baking soda add to pantry
• + ½ teaspoon baking powder add to pantry
• + ½ teaspoon kosher salt add to pantry
• + ½ cup mini chocolate chips add to pantry
• + 1 (4 ounce) package cream cheese, softened add to pantry
• + ½ cup vegetable shortening add to pantry
• + 1 cup marshmallow cream (such as Marshmallow Fluff®) add to pantry
• + 2 cups confectioners' sugar, or more as needed add to pantry