Chocolate Christmas Monster Cookies

Ingredients (12)

• 1½ cups creamy peanut butter
• 1 cup packed brown sugar
• 1 cup white sugar
• 1 stick unsalted butter
• 2 ounces bittersweet chocolate, melted and cooled
• 3 Tablespoons cocoa powder
• 3 large eggs
• 1 Tablespoon vanilla extract
• 4½ cups old fashioned rolled oats
• 2 teaspoons baking soda
• 1 cup semi sweet chocolate chips
• 1 cup red and green M & Ms, plus more for the top of the cookies