In a large baking dish, lay the salmon fillets in a row.
Sprinkle fish with salt and top with 1 Tbsp. Thai sweet chili sauce. Brush to coat fish with sauce evenly on top, bottom, and sides.
Cover and let marinate in the refrigerator for at least 2 hours, or overnight (up to 24 hours).
Turn on the oven's broiler on High and position the top oven rack 5 to 6-inches below the heat source.
Line a large baking sheet with parchment paper or aluminum foil, spray with cooking spray and place salmon, skin side down (if any). Coat with remaining marinade from the dish (if any).
Broil for 8 minutes, rotating the baking sheet once.
Remove from oven and brush top of each fillet with 2 tsp. of Thai sweet chili sauce. Then return to oven and broil for another 5 minutes or until sauce on salmon is caramelized.
Serve with green onions, extra sauce (if desired).