Can you put something on the plate that they do like and will eat? Like maybe it's mashed potatoes and tomato sauce or something foolproof like that. And don't insist they eat everything, just limit the time the plate is in front of them (15-20 mins is long enough). Then if they complain later that they're hungry, put the same plate of food in front of them - or offer something else that's plain (like bread and butter). Eventually they will get the idea.

We have a rule about having to have at least one mouthful of each thing on the plate but then if you choose to not eat it, that's ok. It means things DD didn't like the look of often got eaten cos it turned out it tasted good!

BTW - steak and veggies is hard work for a kid - there's lots of chewing involved - that would be a bit wearing after a long day of playing and having fun! Could you mince the steak up and serve it as a patty? Might go down a bit more happily...