Preheat and prep: Heat your oven to 400°F (200°C).
Line a baking sheet with parchment paper or lightly oil it to prevent sticking.
Pat dry the salmon: Use paper towels to remove surface moisture. Dry fish browns better and stays firm.
Make the lemon-dill mixture: In a small bowl, combine lemon juice, lemon zest, dill, garlic, olive oil, salt, pepper, and Dijon if using. Stir until well blended.
Season the fillets: Place salmon on the prepared sheet. Spoon the lemon-dill mixture over each piece, coating the top evenly.
Bake until just done: Roast for 10–12 minutes, depending on thickness.
The salmon should flake easily with a fork and look slightly translucent in the center. Aim for 125–130°F (52–54°C) for moist, medium doneness.
Rest briefly: Let the salmon sit for 2 minutes out of the oven. This helps the juices settle.
Finish and serve: Add a squeeze of fresh lemon and a sprinkle of dill or parsley. Serve with steamed asparagus, roasted broccoli, or a simple mixed salad.