Instructions

• Place 1 stick (1/2 cup) of the butter in a small skillet over medium heat. Cook, stirring occasionally, until the butter browns and becomes fragrant, about 3–4 minutes. Remove from the heat, pour the browned butter into a heatproof bowl, and freeze for 10–15 minutes.
• While the browned butter chills, preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.
• If not already crushed, put the mini pretzel sticks in a bag and crush them to small pieces.
• In a large mixing bowl, beat together the remaining stick (1/2 cup) of room-temperature butter, the cooled browned butter from step 1, and the 3/4 cup light or dark brown sugar until combined and smooth.
• Add the 2 large eggs one at a time, beating after each until incorporated. Beat in the additional egg yolk, then stir in the 2 teaspoons vanilla extract until combined.
• Add the 2 1/4 cups all-purpose flour, 1 teaspoon baking soda, and 1 teaspoon kosher salt. Mix just until the dry ingredients are incorporated and no large streaks of flour remain.
• Fold in 3/4 cup of the holiday M&M’s, the 1 cup crushed mini pretzels, the 1 cup semi-sweet chocolate chips, and the 1/3 cup dark chocolate chunks until evenly distributed. Reserve the remaining M&M’s (about 1/2 cup) for topping.
• In a small bowl, combine the 1/3 cup granulated sugar and 2 teaspoons cinnamon. Scoop or roll the dough into rounded balls about 2–3 tablespoons each, then roll each ball in the cinnamon-sugar mixture. Place the coated dough balls on the prepared baking sheet spaced about 3 inches apart.
• Bake the cookies for 8 minutes. Remove the pan from the oven, rotate the pan, and gently press the reserved M&M’s into the tops of the cookies. Return to the oven and bake 2–3 minutes more, until the edges are set but the centers still look slightly soft.
• Remove the baking sheet from the oven and let the cookies cool on the baking sheet until they firm up (they will continue to cook slightly as they cool).
• Serve warm or let cool completely and store in an airtight container for up to 4 days.