For fillets of fish I usually use tilapia or salmon, (4 fillets)
2 tsp salt
1 tsp ground pepper
1 tsp chopped rosemary
mix for seasoning
take a rectangle of foil to wrap each fillet in, pour 1 tsp of olive oil and pour it on the foil where the fillet will be, place fillet on top of oil, cut a lemon in half and use one half to squeeze lemon juice on top of fish, then use the seasoning you've prepared to sprinkle on top, thinly slice other half of lemon and place a slice or two on top of the seasoned fish, fold foil over and double roll each edge. poke a hole to vent, place on hot grill for 12 minutes each side, unwrap, enjoy.
I usually add some grilled squash and zucchini for a side and put the fish on a bed of rice.