Trim the asparagus and mince the garlic. Zest and juice the lemon, setting both aside for later.

Heat the olive oil in a large skillet over medium-high heat. When the oil shimmers, add the salmon fillets skin-side down. Cook for about 5-6 minutes until a golden crust forms, then flip gently and cook for another 4-5 minutes until just cooked through.

Remove the salmon from the skillet and set aside on a plate. In the same skillet, add the trimmed asparagus and sauté for about 3-4 minutes until they start to soften.

Melt the butter in the skillet over medium heat. Once it bubbles, add the minced garlic and cook for just a minute until fragrant, but not browned. Stir in the asparagus, then pour in the lemon juice and zest. Season with salt and pepper to taste.

Gently reintroduce the salmon to the pan, coating it in the lemon-garlic sauce, allowing it to warm through for a minute. Sprinkle with freshly chopped parsley before serving.