In a large bowl, cream together the butter, peanut butter, brown sugar, and white sugar until smooth. Beat in the eggs one at a time, then stir in the corn syrup, water, and vanilla.
Combine the flour, baking soda, and salt; stir into the peanut butter mixture. Fold in chocolate chunks. Drop by 1/4 cupfuls 3 inches apart onto ungreased baking sheets.
Bake for 12 to 14 minutes in the preheated oven, or until edges are golden. Allow cookies to cool for 1 minute on the cookie sheet before removing to wire racks to cool completely.
