I actually don't make the vegan version for us because we can eat butter. But I have made this with Earth Balance (which is vegan) many times and it has always turned out great. I have never made this without the bread crumbs, though. I think they provide a nice contrast in texture to the soft and creamy macaroni, but if not everyone will eat the bread crumbs, I am sure you can leave a square of the baking dish free of them.