How large can a tornado get? (recorded, storm)

[TeDavionj987]

Theoretically speaking, I was just watching “Into the Storm”(one of my favorite movies) and the thought just popped up in my head the largest tornado ever recorded was the El Reno Tornado which had a width of a mind-boggling 2.6 miles wide which is very large but what’s stopping a 10-mile wide tornado from forming? Like is there some limit on how big they can get or the ingredients just aren’t there in abundance enough to creat a whirlind that large?