Start by browning your butter, place the butter in a sauce pan over medium heat and allow to melt down and brown. This will take about 10 minutes. Once browned remove from heat and allow to cool.
Preheat oven to 350 degrees and line a large baking sheet with parchment paper.
Place browned butter and little bits from the pan into a stand mixer along with the brown and granulated sugar. Beat to combine then add egg and vanilla beating to combine.
Add your flour, cold water, pudding mix, baking soda, corn starch, salt. Continue mixing with the mixer until combined.
Fold in the Reese's, snickers and m&'m's until just combined.
Scoop the cookies onto your prepared baking sheet and place them in the refrigerator to cool for 1 hour. I like to add some extra chopped candies to the tops of the cookies for extra color.
Bake in the oven for 15 minutes and move the cookies to a wire rack to allow them to cool down.