Oatmeal Sandwich Cookies - Master recipes

Ingredients

• 1-1/2 cups shortening -
• 2-2/3 cups packed brown sugar -
• 4 large eggs, room temperature -
• 2 teaspoons vanilla extract -
• 2-1/4 cups all-purpose flour -
• 2 teaspoons ground cinnamon -
• 1-1/2 teaspoons baking soda -
• 1 teaspoon salt -
• 1/2 teaspoon ground nutmeg -
• 4 cups old-fashioned oats -
• Filling: -
• 3/4 cup shortening -
• 3 cups confectioners' sugar -
• 1 jar (7 ounces) marshmallow creme -
• 1 to 3 tablespoons 2% milk -