Whisk the soy sauce, honey, rice vinegar, grated ginger, minced garlic, and black pepper in a small bowl to make the marinade.
Coat the salmon fillets all over with the marinade, place skin-side up, and refrigerate for at least 30 minutes or up to overnight.
When ready to cook, remove the fillets from the marinade and pat them dry with paper towels.
Pour the reserved marinade into a small saucepan and bring to a boil over medium heat, then simmer until reduced by about half, about 5 minutes; set aside to cool slightly.
Heat a skillet over medium-high heat. Rub or brush the salmon with the olive oil on all sides.
Place the fillets skin-side down in the hot skillet, reduce the heat to medium, and cook until the skin is crisp and the fish is mostly cooked through, about 5 minutes.
Flip the fillets and cook for another 3 minutes, or until the salmon is opaque and flakes easily; remove from the pan and let rest 5 minutes.
Brush the reduced marinade (glaze) over the rested fillets and garnish with toasted black sesame seeds and fresh cilantro leaves before serving.
