Heat olive oil in a cast-iron skillet over medium-high heat until shimmering. This ensures a good sear on the salmon skin, preventing sticking.

Season salmon fillets with salt and pepper. Place them skin-side down in the skillet, pressing gently to ensure even contact.

Cook salmon for 4-5 minutes, until the skin is crispy and golden brown. You'll hear a gentle sizzle as it cooks.

Carefully flip the salmon and reduce heat to medium. Cook for another 3-4 minutes until the salmon is opaque.

Remove salmon from the pan and set aside. Add butter to the skillet, allowing it to melt and turn slightly golden.

Add minced garlic to the melted butter, stirring until fragrant, about 30 seconds. Avoid browning the garlic to prevent bitterness.

Stir in lemon juice and zest, scraping up any browned bits from the pan for added flavor.

Return the salmon to the skillet, spooning the lemon butter sauce over the fillets. Garnish with chopped parsley before serving.