Caramelized Onions on My Hot-Dog

I often put caramelized onions on my Hot Dogs. People always tell me that you can only use Vidalia onions to caramelize and put on your Hot Dog. My response is you can use any type you want. I use an assortment of red, yellow and Vidalia's. The way I caramelize them is, I stand the onion up on its roots, slice it down the middle, then lie them face down and slice it thin. Put a little oil in a pan and saute them up (I do not put any thing else in, no sugar, no butter).
I am off to make some Hot Dogs right now.