Preheat oven to 325°F. Grease a half sheet pan.
In a large bowl, whisk together the melted butter, brown sugar, and white sugar until well combined.
Add the molasses, eggs, egg yolks, vanilla, and sea salt. Whisk until smooth and well combined.
Add the flour and baking soda. Mix until just combined. Do not overmix.
Fold in your desired mix-ins.
Spread the dough evenly into the prepared half sheet pan.
Bake at 325°F for about 20 minutes, or until the edges are lightly browned and the center is no longer shiny.
Let cool before slicing into squares or bars.
