First get your barbeque going, with the coals piled up high on one side
so it's super hot and low on the other side for a more gentle heat to
give you some control.
With a sharp knife, score each of your fish all over on both sides,
about 1cm deep. This helps the flavours to get into the fish and will
allow the heat right in so the fish gets cooked evenly right down to
the bone.
Get a big chopping board ready. Roughly chop the oregano leaves then
scatter them over the board. Sprinkle over a generous amount of salt
and pepper. Roll the fish over board, pushing them down and rubbing the
flavourings into the slashes.
Place fish on to the hot side of the barbie to give them a bit of
colour. You’ll be making your salsa on the cooler side (or on your
hob). Just heat a little olive oil in a frying pan, add the chopped
olives and warm them through for a minute or so. Add the garlic, chilli
and rosemary sprigs, give it a good toss and gently fry while you
finish cooking your fish.
After about 4 minutes turn the fish over by easing them off the grill
with a fish slice – be patient otherwise they will stick – and cook for
another 4 minutes until cooked and moist on the inside, with a crispy
skin on the outside.
Remove and discard the sprigs of rosemary from the frying pan; they
will have released lots of flavour so they've done their job. Add the
chopped tomatoes to the pan and toss. Squeeze in the lemon juice and
add the parsley leaves. Give the salsa a taste. Olives are usually
quite salty so you probably don’t need any more salt but that's your
call. I might add a little pepper though. Once everything is warmed
through, take the pan off the heat.
Remove the fish to a plate. To make sure they are cooked, pull a bit of
the meat away from the bone. If it comes away easily, you're in
business.
Serve the fish simply with some salsa spooned over the top.
PS If you've got any leftovers, what I like to do is pull the fish away
from the bone and flake it into a bowl. Toss with the leftover salsa,
add some extra torn parsley leaves or peppery rocket, and serve with
some nice bread.