Preheated the oven to 350°F., In a large mixing bowl, beat together the butter and sugars. Add the egg and vanilla, and beat until smooth. Stir in the remaining ingredients, mixing until everything is well combined., Drop the dough by heaping tablespoonfuls (a tablespoon cookie scoop works well here) onto lightly greased or parchment-lined baking sheets, leaving about 1 1/2" between each ball of dough., Bake the cookies for 12 to 15 minutes, or until they're golden brown. Remove them from the oven, and cool on a rack., Store cookies in an airtight container, at room temperature, for several days. If you want to keep them very soft and chewy, store them with a brown sugar saver. Freeze for longer storage.