Preheat oven to 375°F. Line a baking sheet with foil or parchment.
Pat the salmon completely dry with paper towels — moisture prevents a good sear and slows cooking.
Place salmon skin-side down on the prepared sheet.
Drizzle with olive oil and use your fingers to coat the entire fillet. Season generously with salt.
Bake 12–15 minutes depending on thickness. The salmon is done when it flakes easily with a fork at the thickest point and the flesh has turned from translucent to opaque.
Do not overcook — salmon keeps cooking after it leaves the oven. Pull it when the very centre still looks barely underdone.