Place salmon fillets into a large zippered food storage bag or shallow dish/container. In a medium bowl, whisk soy sauce, honey, sesame oil, garlic, and ginger together. Pour about half of the mixture (just eyeball it) over salmon. Turn salmon to coat. Seal the bag/cover the dish and refrigerate for at least 15 minutes and up to 4 hours.

Meanwhile, preheat oven to 375°F (191°C). Line a baking sheet with aluminum foil, parchment paper, or a silicone baking mat. Set aside.

Line the marinated salmon fillets on the baking sheet, skin side down. You can hold onto this used marinade—see step 5. Bake salmon for 15–20 minutes or until done, which is 10 minutes per inch thickness measured from the thickest part of the fillet. (Salmon is considered done when an instant read thermometer reads the center of the thickest part as at least 145°F (63°C).) Feel free to turn your oven to broil for the last minute to really crisp the edges.

Meanwhile, as the salmon bakes, pour the remaining unused marinade into a small saucepan or skillet over medium-high heat. If you want, you can add the remaining (used) marinade as well. Bring to a boil, and then reduce heat to medium-low and simmer for 3–4 minutes or until slightly thickened. Keep a close eye on it because it can quickly burn. It will bubble up a lot as it reduces. Remove from heat.

Drizzle thickened glaze over baked salmon and serve with optional garnish.

Leftovers keep well in the refrigerator for a few days. Reheat to your liking.