The food sounds fine, but your dog has learned that you will give him food, as long as he is reeeeeeeeeally persistent. You might want to try a mild negative reinforcer, like a can with pennies in it. Every time he barks, shake it. You could also try giving him a time out in another room.
The number one thing though, is that if you want him to stop, you must decide that you will refrain from giving him a morsel
no matter what. If you're going to give up and give him a treat, you may as well do it immediately. After all, he's a dog, he's got nothing better to do than bark at you if there's even a slim chance he'll get a nice snack out of it.
Oh, and: you'll find lots of great threads here about how to make your sweetie's food more interesting. You can give him lots of nice, healthy, varied meals, as long as you do it on your terms, not his.