I have a one year old Brittany. He is intelligent and gentle. But he seems to think responding to my requests is optional.. If I have chicken in my hand no problem, but otherwise nope he won't come. He seems nervous of me, probably because I am giving off "I am annoyed with you" signals.
My dog is a feral animal, with very strong hound tendencies. That means he has definite ideas about what he'd prefer at any given moment. In order to have that reliable obedience took years and was as much or more a function of 'trusting' me as it was about earning goodies. Earning goodies helps develop that bond, rather than take away from it and will show dividends later on.
Consider this: if you had a friend who asked 'favors' of you, but rarely gave anything in return - maybe not even a 'thank you', how eager would you be to keep doing favors? But if that friend regularly gave you something you valued in return, you'd be much more willing to keep helping them. Its not a lot different with dogs; they don't want to keep giving/giving/giving without anything in return. Some dogs are more forgiving in that regard and will work for very little reward, while others are much more 'what's in it for me' end of the scale. Kinda like people, eh?
This doesn't mean that you *always* have to give treats, but what you need to do is teach the dog that payment will come. The best way is to use intermittent reinforcers; that means that the dog doesn't know when the reward will come, so responds each time "just in case". It's the same principle that keeps people using slot machines or gambling - each time, they hope for a pay-off.

There is good information in the training stickies, as well as around the web and on Youtube; make sure the trainers are using positive reinforcement, not bribery or 'corrections'. You might look into clicker training. Or, you could invest in a couple of sessions with a trainer who uses positive reinforcement.
He stresses me out.. To the point we are considering rehoming him which makes me very very sad. How do you go from rewarding with food to a dog just listening and doing? If there is no chicken my dog isn't going to do as you ask..
He's really young yet, about the equivalent of a two-year old. How reliable is a two-year-old in doing what they're asked?

Unless you have candy, of course. With persistence and patience, he will get better - especially after he gets through adolescence. He may always have that independent streak, but in my opinion that's a more interesting dog to develop a bond with.