Picky Eater

Parker used to eat anything we would give him. When he hit the age of two, this changed a little, but he would still eat his veggies, and usually anything that we made, and could talk him into eating. He's always been up and down with how much he ate (depending on growth spurts, his mood, health, etc). Recently....in the past few months....his tastes have changed. We started noticing this when we gave him his favorite meal for lunch- chicken nuggets, macaroni and cheese, and peas, and he gagged on the macaroni and cheese and literally lost his lunch! No more macaroni and cheese. At the next meal where we had peas, he refused to eat them and I had to bribe him with ice cream to take one bite...well, that one bite didn't stay down and he lost it again! No more peas. He used to love to help me make homemade pizza and eat tons of it....now he just likes to help and refuses to eat it. He used to beg us for peanut butter and jelly toast....now he asks for plain bread. (Gross)! He used to love to go to the "Taco Store" (El Mezcal) and eat tacos....now when we go, he asks for chicken nuggets and french fries. His favorite food used to be spaghetti...the other night I made it and he took two bites. He used to love pizza of all kinds....now he'll only eat Tony's frozen party pizzas. (Bleck)! He won't even eat applesauce anymore! What is wrong with my child!!!??? I'm trying any new recipe I can find, but nothing seems to be a good fit with Parker's appetite!!! I need some ideas!!??