Creating Christmas Monster Cookies is easy and fun! Follow these simple steps to whip up your batch of festive treats:

1. Preheat Oven: Preheat your oven to 350°F (175°C) and line baking sheets with parchment paper.
2. Cream Butter and Sugars: In a large bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.
3. Add Peanut Butter: Mix in the peanut butter until well combined.
4. Incorporate Eggs and Vanilla: Beat in the eggs one at a time, followed by the vanilla extract. Ensure everything is well blended.
5. Combine Dry Ingredients: In a separate bowl, whisk together the oats, flour, baking soda, and salt.
6. Mix Dry Ingredients: Gradually add the dry ingredients to the creamed mixture, stirring until just combined.
7. Add Chocolate Chips and M&M’s: Fold in the chocolate chips and M&M’s (and nuts, if using) until evenly distributed.
8. Scoop Cookies: Use a cookie scoop or tablespoon to drop cookie dough onto the prepared baking sheets, spacing them about 2 inches apart.
9. Bake: Bake in the preheated oven for 10-12 minutes, or until the edges are lightly golden and the centers are set.
10. Cool: Remove from the oven and let the cookies cool on the baking sheets for 5-10 minutes before transferring them to wire racks to cool completely.

These steps will guide you in creating incredible Christmas Monster Cookies that will delight both you and your guests!