Preheat the oven to 400 degrees.
Put flake salt on both sides of the fish and inside the fish. Salt to taste! Remember you can always add salt once it is almost all the way cooked and this kind of fish can take a lot of salt!
Squeeze 1 1/2 lemons on each fish. Basically half a lemon per side and inside.
Make three slits on top of the fish in a diagonal design.** Tip make the slips from the base of the knife up.
Insert one piece of garlic into the diagonal slit using all 6 slices of garlic.
Insert 3 sprigs of rosemary diagonal inside each fish.
Cook fish uncovered in a 400 degree for 20 minutes. Then, turn the broiler on high or 450 degrees and broil for another 5 minutes or until golden brown and crispy skin.