The bad news for parents of older tots that are already walking is that the number of times you have to introduce a new food increases from six to 89. We know, that's a lot, but think of it this way: if you serve one bite of the new food with every single meal the child eats (say peas, a commonly hated food), it'll only take about a month for their palette to adjust and for them to realize they actually like it. It seems like a long time, but you can do it with multiple foods at once, and it can get them eating something seriously healthy by choice.
Pro tip: the one-bite rule is the ultimate bargaining trick — if you "concede" and let them eat "just one bite," they'll think they're winning some kind of battle. Little do they know . . .