but barbeque sauce/marinade is a wonderful thing
I use lots of garlic, and soy sauce (tamari) and
a bit of balsamic vinegar and some fresh herbs,
and lots of onions too, and a bit of red pepper
(cayenne, chili, paprika and / or tabasco sauce)
you don't need ketchup or tomatoes in it, but
that kind of sauce is good too.

throw a few ears of corn on the barbie grill
(peel back the husk and remove the silk first,
then replace the leaves and soak in water before
tossing on)