Preheat the oven to 350°F. Line two baking sheets with parchment paper.
Add the butter to a saucepan and cook over medium-low heat until melted, golden brown, and nutty in aroma. Pour into a large mixing bowl and let cool for a few minutes.
Add the coconut sugar, monk fruit sweetener, egg, and vanilla extract to the browned butter. Beat with a hand mixer until light and fluffy.
Fold in the flour and baking powder, mixing until no dry flour remains.
Stir in the M&Ms, crushed pretzels, crushed potato chips, and mini chocolate chips, reserving some chocolate chips for topping.
Scoop the dough into balls (about 1½ inches wide) and place 6 cookies per baking sheet, spacing them about 2 inches apart. Gently press each ball into a thick disc.
Sprinkle reserved chocolate chips on top and bake for 10–12 minutes, until the edges are set and the centers are still soft.
Remove from the oven and immediately add any additional toppings while the cookies are warm.
Let cookies cool completely before serving.