Preheat the oven to 275°F to 300°F
Place the salmon on a baking sheet or in an oven-safe dish
Add a small amount of water, broth, or butter to keep it moist
Cover the salmon loosely with foil
Heat for 10 to 15 minutes, or until warmed through
Reheat on the stovetop over low heat in a covered pan if preferred
Use a microwave on low power in short intervals if needed
Check that the salmon reaches 145°F internally
Avoid overheating to prevent drying out