Chewy Chocolate Chip Cookies

How to make chocolate chip cookies from scratch at home. Recipe below Ingredients * 4.5cups (all-purpose flour (spooned & leveled) * 2 teaspoon baking soda * 1 tablespoon cornstarch* * 1 teaspoon salt * 1.5 cups unsalted butter, melted & cooled 5 minutes* * 1.5 cups packed brown sugar * 1 cup granulated sugar * 2 large egg + 2 egg yolk, at room temperature * 4 teaspoons pure vanilla extract * 2.5 cups semi-sweet chocolate chips or chocolate chunks