It is a phase. Some kids at this age are "too busy to eat" He is also learning that he has the ability to control situations. I wouldn't give him all the control- give him 2 choices- if he does not decide- pick one for him. If he doesn't eat, save it until he is hungry. Even if it means feeding it to him at the next meal! Kids will not starve- when he is hungry he will eat.
We have the "bite rule" at our house- you have to take one bite for every year of age of what has been made for the family meal- then you can have xyz (you can use other things besides treats- we use a favorite book, extra time in a bubble bath, a call to grandma) in his case he would have to take 2 bites, then he could have a treat or something.
If you don't nip it in the bud you will be making one meal for your family and another one for him for a very long time!
having him help in the kitchen is another great idea. kids love to play with their food!
Our Ped says if they are not eating well- we should feel free to give them some pedisure or carnation instant breakfast (which is cheaper and you can get the no sugar added)