Preheat the oven to 350 degrees F and line two cookie sheets with parchment paper.
Microwave the butter for about 40 seconds to just barely melt it. It shouldn’t be hot – but it should be almost entirely liquid. Cool for a minute or two until room temperature.
10 tablespoons unsalted butter
Whisk together the flour, baking soda and salt in a medium bowl.
2 cups unbleached all-purpose flour, ½ teaspoon baking soda, ½ teaspoon fine sea salt
Combine the granulated sugar, brown sugar, and melted butter in the bowl of a stand mixer fitted with the paddle attachment. Beat on medium speed for 2 minutes until well blended.
½ cup granulated sugar, ⅔ cup light brown sugar
Beat in the egg, egg yolk and vanilla until light and creamy.
1 large egg, 1 large egg yolk, 1 tablespoon pure vanilla extract
Beat in the flour mixture on low until just combined.
Remove bowl from the mixer and fold in the chocolate chips.
1 ½ cups semi-sweet chocolate chips
Use a 2oz/1/4 cup cream scoop to scoop out the dough onto the prepared cookie sheets, leaving 3" between each cookie.
Bake for 14-16 minutes or until the edges are lightly brown and the tops look just set. Transfer to cookie sheets to wire racks to cool slightly. Serve warm.