This recipe is so simple, I'm inclined not even to put it here. But it works.
I'm sure most of you have made a homemade steak/barbecue sauce, but in the interests of discussion, I give you this:
1 part Ketchup(I use Aylmer because it was on sale, $2.47 for a liter)
1 part apple cider vinegar
1 part worcestershire sauce.

Kind of tangy which I like, although I wouldn't mind a bit of brown sugar in there. Maybe next time. Although next time I'll make it like this and see what happens:
2 parts ketchup
1 part apple cider vinegar
1 part worcestershire sauce

I like this on pork tenderloin. You can always kick it up many notches. Add apricot preserves? Might work...etc.