Preheat the oven to 375 degrees F (190 degrees C).
In a medium bowl, cream together the butter, chocolate syrup, brown sugar and white sugar until smooth. Beat in the eggs, one at a time, then stir in the corn syrup and vanilla. Combine the flour, baking soda and salt; stir into the creamed mixture until just blended. Mix in the chocolate chunks by hand. Drop cookies by 1/4 cupfuls onto ungreased cookie sheets.
Bake for 12 to 14 minutes in the preheated oven. Allow cookies to cool on baking sheet for 5 minutes before removing to a wire rack to cool completely.