In a food processor fitted with a metal blade, pulse lime juice and garlic. Add parsley, cilantro, oregano, red pepper flakes, salt and pepper; pulse until roughly chopped. With the food processor running on low, drizzle in olive oil, process until just combined; set aside.
Preheat an outdoor grill to medium-high OR an oven to 425 degrees. Line a baking sheet with Heavy Duty foil.
Rinse the fish under cold water and pat dry with paper towels. Place fish on the foil-lined baking sheet (roll the edges up around the fish) and remove the pin bones. Drizzle with olive oil and season with salt and pepper.
Slide the fish packet onto the grill; close the lid and grill for 12 to 15 minutes (depending on the thickness of the salmon) or until the salmon flakes easily. Do not over-cook! Carefully, remove the fish packet from the heat back onto the baking sheet. Spoon chimichurri sauce over the cooked fish and serve.
Alternately, cook the fish on the foil-lined baking sheet in the oven for 12-15 minutes or until the salmon flakes easily. Do not over-cook!