Preheat oven to 375 degrees F.
Prepare two baking sheets with parchment paper and set aside.
In a medium size bowl, combine flour, salt, and baking soda. Mix well and set aside.
In bowl of stand mixer fitted with paddle attachment, beat melted butter, sugars, and maple syrup at low speed until thoroughly combined
Add yolk, milk, and vanilla to mixture and mix until throughly combined, approximately 1-2 minutes.
Add 1/2 of flour mixture to ingredients and mix on low until just starting to combine. Add remaining flour mixture and mix until just combined. Do not overbeat. You want to limit the amount of air you work into this dough.
Fold in chocolate chips and mix until just combined.
Leaving about 2 inches between each cookie, scoop and place dough onto baking sheet, approximately one tablespoon for each cookie.
If desired, sprinkle the top of each cookie with a few flakes of sea salt just prior to baking.
Baking only one sheet at a time, bake for approximately 12 minutes or until cookies are starting to brown and turn golden.
Remove from oven and cool cookies on baking sheet 3 minutes. Using wide, thin spatula, transfer cookies to wire rack and let sit until crisped and cooled to room temperature.