Preheat your oven to 425°F (220°C). On a baking sheet, toss the trimmed asparagus with olive oil, salt, pepper, and lemon zest. Spread them out in a single layer and roast in the preheated oven for about 15-20 minutes, until tender and slightly crispy.

While the asparagus is roasting, place the diced potatoes in a large pot and cover with cold water. Add a pinch of salt. Bring to a boil over medium-high heat, then reduce to a simmer and cook for about 15-20 minutes, or until the potatoes are fork-tender. Drain the potatoes and return them to the pot. Add heavy cream, butter, salt, and pepper. Mash until smooth. If desired, stir in sour cream for extra creaminess.

In a large skillet, heat olive oil over medium-high heat. Season the salmon fillets with salt and pepper. Once the oil is hot, add the salmon skin-side down and cook for 4-5 minutes, without moving it, until the skin is crispy. Carefully flip the salmon and add butter and minced garlic to the pan. Cook for an additional 3-4 minutes, basting the salmon with the melted garlic butter. Squeeze the lemon juice over the salmon just before serving.

On each plate, serve a generous scoop of creamy mashed potatoes, a portion of roasted asparagus, and a salmon fillet drizzled with garlic butter. Garnish with chopped fresh parsley and extra lemon wedges if desired.