Preheat an oven to 350 degrees F. Combine the flour, baking soda and salt in a large bowl. Beat the butter, granulated sugar and brown sugar together until light and fluffy (about 3 minutes) on medium speed. Beat in the eggs, one at a time, then add the vanilla.
At a low speed, beat in the dry ingredients in batches, until just blended, do not over beat or the dough will get tough. Stir in the chocolate chunks and chopped chocolate using a wooden spoon until well combined. Wrap the bowl with plastic and chill dough 30 minutes or overnight.
Shape or scoop into 2-inch balls using a spoon or ice cream scoop. Place on cookie sheets, about 3 inches apart. (About 6 cookies per tray with 2 trays per batch.) Flatten them slightly and bake until golden brown around the edges, about 15 to 18 minutes. Let cool on tray about 3 minutes. Transfer the cookies to a cooling rack and cool completely.
To make sure the cookies bake evenly, move the cookies on the upper rack to the lower rack and vice versa and rotate the sheets from front to back halfway through the baking time.
Claudia Sidoti for Cooking Channel