I do the same as Spixie. I serve options to an extent. My daycare meals consist of batch cooking the dinners I make for my family. Usually a protein, a starch and a vegetable. I always offer carrot/celery sticks too. If it's summer and hot we have sandwiches, a raw veg and a fruit. Lots of options. If someone is stubborn enough to not want any of those foods then they can wait until snack.

That said, my children have a very wide palette (well, my daughter is a bit picky) and most of the kids see the others eat and follow suit.