In a small bowl, whisk together the soy sauce, honey, rice vinegar, sesame oil, minced garlic, and grated ginger until well combined.
Place the salmon steaks 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 grill or a non-stick skillet over medium-high heat. If using a skillet, lightly grease with cooking spray or a small amount of oil.
Remove the salmon from the marinade, reserving the marinade for later. Cook the salmon steaks for about 4-5 minutes on each side, or until they are cooked through and have a nice glaze.
While the salmon is cooking, pour the reserved marinade into a small saucepan and bring to a boil. Reduce the heat and simmer for about 5 minutes until slightly thickened.
Serve the salmon steaks drizzled with the thickened marinade, and garnish with sliced green onions and sesame seeds.