Preheat the oven to 180 degrees.c.
Wash the fish well under cold running water ensuring to clean the inside of the fish.
Pat the fish dry using a paper towel and place the fish in an ovenproof baking dish. Using a knife cut 3 slits in each fish diagonally across the belly. (until the bone).
Rub the Maggie Seasoning all over the fish on both sides. (using gloves)
Place 1 slice of lemon, a slice of onion, 2 slivers of garlic and a sprig of thyme in each slit for each fish.
Place the remaining onions, lemons, thyme and garlic inside the fish (stuffed in the fish belly).
Drizzle the olive oil on top of the fish and place in the oven for 20-25 minutes.
For the chimichurri sauce- place all the sauce ingredients in a bowl and mix well. set aside.
For the garnish - heat a grill pan on high heat and place half the lemon flat side down for 2 minutes until there are grill marks on the lemon. serve the roasted fish with the grilled lemon and some chopped parsley on the top.
Place the lettuce cups on a plate and add the fish morsels with a drizzle of chimichurri in each one. Otherwise place the fish with the sauce on the table and allow everyone to create and enjoy their own fish lettuce wraps.