3 1/3 cups all-purpose flour, 3/4 teaspoon baking soda, 1/2 teaspoon salt, 16 (2 sticks) tablespoons margarine melted and cooled, 1 1/4 cups packed light brown sugar, 1/2 cup sugar, 2 large eggs, 2 large egg yolks, 1 tablespoon vanilla extract, 2 cups chocolate chips.
1. Adjust oven rack to middle position. Preheat oven to 325 degrees. Melt margarine and set aside. Whisk flour, baking soda, and salt together in medium bowl and set aside.
2. Beat butter and sugars in large bowl with electric mixer 1 to 2 minutes. Beat in the eggs and vanilla until combined (about 30 seconds), scraping bowl and beaters as needed.
3. Reduce mixer speed to low and gradually add flour mixture until combined. Mix in chocolate chips.
4. Fill a 1/4 measuring cup with dough, scrape onto parchment lined baking sheet with small spatula. Bake 17 to 20 mintues until edges are golden brown and center is soft and puffy. Rotate baking sheets halfway through.
5. Cool and enjoy.