Melt butter in a medium skillet over medium heat. Cook 4-5 minutes, or until the butter starts to brown. Remove from heat and let cool slightly.

Preheat the oven to 325.

In a large bowl or the bowl of stand mixer, mix together the butter and sugars. Add the egg, egg yolk, and vanilla and mix until combined. In a separate bowl combine the flour, baking soda, and salt. Add the flour to the wet mixture and stir to combine. Gently stir in the chocolate chips.

Line your baking sheet(s) with parchment paper or a Silpat liner. Roll about 1 and 1/2 tablespoons (I used my cookie scoop) dough into a ball and pull each ball into two pieces using your hands. Place one half of the dough ball, rough side down, on the baking sheet and then place the other half, rough side up, on top of the first half and press together slightly. Sprinkle each cookie with sea salt.

Bake 12-15 minutes, or until very lightly browned around the edges. The middles of the cookies will still be soft. Let cool on baking sheet for 5-10 minutes, and then remove to cooling rack to cool completely.