That's such a lovely age - congratulations. My kids have always enjoyed participating in the cooking and they love theme parties. Does your daughter like this?
Anyway, one of the things that came to mind is a variation on this:
Hot pot - Wikipedia, the free encyclopedia
You could have a variety of ingredients sliced and prepped with the stock pot in the center of the table on a hot plate. Then everyone could select what they want to cook. You could have plenty of cooked rice and perhaps buckwheat noodles on the side, along with a variety of small dessert items. Maybe individual little tea pots and different teas. Plus an assortment of different sauces - hot, spicy, sweet, etc.
If she will have guests the same age, have on hand some chopsticks for each child. You could decorate with some paper lanterns and maybe get a little Chinese-style hair ornament for each girl.
You could do a similar thing with and Italian theme and build-your-own pizzas. Having a lot of different toppings prepped and ready makes it really fun. You could serve different pastas and sauces, too.