Preheat your grill or oven to 400°F (200°C). If using a grill, lightly oil the grates to prevent sticking.
In a small bowl, whisk together the honey, pineapple juice, soy sauce, Dijon mustard, minced garlic, and ground ginger until well combined.
Season the salmon fillets with salt and pepper on both sides.
Place the salmon fillets in a shallow dish and pour half of the honey-pineapple glaze over them, reserving the other half for later. Let the salmon marinate for about 15-20 minutes.
If grilling, place the salmon skin-side down on the grill and cook for about 6-8 minutes. Brush with the reserved glaze halfway through cooking. If baking, place the salmon on a lined baking sheet and bake for 12-15 minutes, brushing with the reserved glaze halfway through.
The salmon is done when it flakes easily with a fork and reaches an internal temperature of 145°F (63°C).
Remove the salmon from the grill or oven and let it rest for a few minutes. Drizzle any remaining glaze over the top and garnish with chopped green onions before serving.