Preheat oven to 350 degrees F.
Heat butter into a small saucepan over medium heat. Stir for about 5 minutes until butter is a deep golden brown. Remove heat and let cool for 5 minutes.
Place browned butter and the little brown bits from the bottom of the pan into a stand mixer. Add the brown and granulated sugar. Beat to combine butter and sugar and then add egg and vanilla. Mix.
Add all-purpose flour, cake flour, JELLO pudding mix, baking soda, corn starch, salt and chocolate chunks. (Chocolate chips work fine too!) Blend on low until just combined.
Using a cookie scoop (or just a spoon if you don't have a scoop!), place dough balls onto prepared baking sheet about 1 inch apart. Sprinkle each cookie with a pinch of sea salt and bake for about 10 minutes. Remove from oven and let cool on pan for 10 minutes.