In a small bowl, whisk together honey, soy sauce, minced garlic, grated ginger, olive oil, sesame oil, black pepper, and red pepper flakes (if using) until well combined.
Place the salmon fillets in a shallow dish and pour the marinade over them. Cover and refrigerate for at least 30 minutes, or up to 2 hours for more flavor.
Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Remove the salmon from the marinade and place the fillets skin-side down on the prepared baking sheet. Reserve the marinade for later.
Bake the salmon in the preheated oven for 12-15 minutes, or until the salmon flakes easily with a fork.
While the salmon is baking, pour the reserved marinade into a small saucepan. Bring it to a boil over medium heat and let it simmer for about 5 minutes, or until it thickens slightly.
Once the salmon is done, remove it from the oven and brush the thickened glaze over the top of each fillet.
Return the salmon to the oven for an additional 2-3 minutes to caramelize the glaze.
Remove from the oven, garnish with sliced green onions and sesame seeds, and serve immediately.