• Prepare a baking sheet by lining it with parchment paper. Set aside.
• In a large mixing bowl, cream butter and powdered sugar together for about 2 minutes or until creamy.
• Add flour and beat again. Dough will be powder-like, however, it will take shape after beating for about 2-3 minutes.
• Place dough covered in refrigerator for 30 minutes.
• Preheat oven to 350ºF.
• Form 1-inch balls of dough and place them on your prepared baking sheet.
• Using a flat-bottom glass lightly spray with cooking spray, flatten dough balls until they are about ¼-inch thick.
• Bake cookies for 15-18 minutes or until slightly golden brown. After 5 minutes place cookies on a wire rack.

Decorate

• To prepare frosting, beat shortening in a large bowl until creamy.
• Add powdered sugar and milk in three separate batches, beating after each.
• Add vanilla and beat until smooth.
• Add food coloring gel until desired coloring is reached. This will depend on the type of food coloring gel you are using.
• Transfer frosting to a large pastry bag with a star-shaped tip on it.
• Using black frosting, pipe a mouth on each cookie. I then used a toothpick to fill in the mouth.
• Using blue frosting, create the rest of Cookie Monster’s head, leaving a small part at the top unfrosted for the eyes.
• Put a small amount of frosting on the back of the eyes to secure two of them onto each cookie. Serve.