Create GameObjects in Threads?

So I have a class I'm using in Editor to make a collection of GameObjects. It takes a long time, and there's no update in between items, so it freezes until all items are made. Wanting to speed this up, I moved the code to a separate class, and called that on a thread, but when I run it, I get an error: Internal_CreateGameObject can only be called from the main thread. Constructors and field initializers will be executed from the loading thread when loading a scene. Don't use this function in the constructor or field initializers, instead move initialization code to the Awake or Start function. I'm wondering if there's either a) a means to create these objects in a thread b) a means to update my GUI on the status between GameObject Creations (I've looked at Coroutine but didn't quite get it. c) Application.DoEvents for those familiar with VB.Net.