C.O.
We suffered through this. I personally do not like drama at the dinner table. We finally told my son that if he wasn't finished by the time the adults were, he'd have 15 minutes by the timer to finish his food. WHen the timer went ding, he was done. Now, the first night, we showed him how long that would be, and let him finish on his own with the caution that next time his plate would be cleared from the table after the ding. We also explained that he would not have any other food for the rest of the night. It broke my heart to do it, as I like to feed people; but it seemed to work.
Another thing that worked before homework was a big deal was play time. If he took too long to eat, he got ready for bed and went to bed without after dinner playtime. Interestingly, this didn't work as well as the timer.
Kids do not have the same concept of time we do, sometimes something they can actively see as a reminder that isn't a parent can do wonders.
Now that my son is 6, he finally eats his dinner with the rest of us, and only rarely needs a few minutes at the end to finish up.