In a large zip-top bag, combine honey, soy sauce, rice vinegar, sesame oil, ginger, garlic, green onion, red pepper, pepper, and salt. Zip shut and shake to combine.
Add salmon fillets to the marinade and seal the bag. Set in the fridge for 30-60 minutes, turning once or twice to evenly distribute marinade.
Preheat oven to 425° F. Line a rimmed baking sheet with parchment paper or foil for easy cleanup.
Remove the salmon from the marinade with tongs and place it on the prepared baking sheet, skin side down. Bake about 6-10 minutes*, until 125-130°F internally and opaque in the middle (no raw looking areas). The cooking time may vary depending on the thickness of the fillets. Check the temperature early, if your fillets are thin and small. Do not overcook!
Serve warm with a pad of butter on top, a drizzle of soy sauce, and sprinkle of green onions, if desired.
*If you want more caramelization on the outside of the salmon, position the top rack about 6 inches from the broiler. When your salmon reaches about 110-115°F internally, turn on the broiler. Broil the salmon on the top rack for 2-3 minutes, or until cooked through.