Melt the Butter: Start by melting unsalted butter in a microwave-safe bowl for about 30 seconds until almost melted. Cool for 20 minutes.

Whisk Dry Ingredients: In a large bowl, combine all-purpose flour, baking powder, baking soda, and salt. Whisk until no lumps remain.

Mix Wet Ingredients: In another bowl, whisk together melted butter, dark brown sugar, and granulated sugar. Add eggs and vanilla extract, mixing until smooth.

Combine Wet and Dry Mixtures: Gently fold wet ingredients into dry ingredients until just combined; dough should be thick and slightly sticky.

Add Festive Mix-Ins: Fold in M&Ms, white chocolate chips, broken pretzels, and crushed potato chips evenly throughout the dough.

Scoop Your Dough: Portion out the dough onto a parchment-lined baking sheet, spacing them 2 inches apart, aiming for 1.5 ounces per cookie.

Chill the Dough: Cover the baking sheet and chill the dough in the refrigerator for at least 1 hour.

Preheat and Bake: Preheat oven to 350°F (180°C) and bake cookies for 13-15 minutes until golden around the edges and soft in the center.

Shape and Cool: Let cookies cool briefly, shape with a cookie cutter if desired, and sprinkle extra mix-ins on top before cooling completely on a wire rack.