Chocolate Chip Cookie Bars

From Good Things Catered:

The Best Chocolate Chip Cookie Bars
Adapted from the Best Chocolate Chip Cookies

Ingredients:
2 cups plus 2 Tbsp all-purpose flour
1/2 tsp baking soda
1/2 tsp salt
12 Tbsp (1 1/2 sticks) unsalted butter, melted & cooled until warm
1 c brown sugar, packed
1/2 c granulated sugar
2 large eggs
2 tsp vanilla extract
1 1/2 cups semisweet chocolate chips

Directions:
-Preheat oven to 350 degrees and prepare 8x8 baking dish.
-In medium bowl, combine dry ingredients and set aside.
-In bowl of stand mixer, or by hand, mix butter & sugars until thoroughly combined.
-Beat in egg, yolk and vanilla until combined.
-Add dry ingredients & beat at low speed just until combined.
-Stir in chips.
-Pour into baking dish and lightly pat to even out mixture in pan.
-Place in oven and bake until light golden brown and outer edges start to harden yet center is still soft & puffy (about 30 minutes in my oven).
-Remove from oven and let cool completely before cutting into bars.