Tips or recipes for fussy eater (nearly 4yo)

Does anyone have any tips or good recipes for a nearly 4 yo fussy eater? My son particularly likes bread, and I do make a good and healthy homemade bread, but he eats such a limited diet, I would like to make some more things for him.

I make waffles/pancakes/muffins for breakfast, so that is OK, but lunch is usually a humus sandwich and dinner is tuna potato cakes with broccoli. Sometimes he has a banana mango smoothie during the day or in place of a meal. And that is pretty much what he has EVERY day.

Any ideas about how to help him try more foods? We have tried a sticker chart with limited success. We have tried serving him what we are having and offering no alternative, but dinner just goes in the trash. I try not to let it bother me, but I am just searching for a few more foods that he could eat.