Line a jelly roll pan with parchment paper.
Melt butter in a large microwave safe bowl and let cool a bit.
To the butter, add the sugars and whisk 2 mins.
Add egg and vanilla.
Add dry ingredients and stir in chopped chocolate.
Chill dough overnight or several hours.
Preheat oven to 350°
Weigh into 3 ounce mounds.
Bake 10 mins. At this point mine look a bit unshapely so I use a round cookie cutter to scoot them back into shape and add more chocolate on top. Then I bake them an additional 5 mins.
Remove and top with sea salt.