Before you begin: If you haven’t already, allow the salmon to rest at room temp for about 20 minutes. This tempers the salmon so cold salmon from the fridge doesn’t reduce the heat in the pan. You can skip this step if you’re short on time, but it helps the salmon cook evenly.
Cook the pasta: Cook the pasta according to package directions, reserving 1/3 cup of pasta cooking water before draining.
12 ounces uncooked penne pasta
Sear the salmon: Pat the salmon dry and season with kosher salt and pepper. Heat the oil or butter in a deep skillet over medium-high heat, until it's hot and rippling. A drop of water will sizzle on the surface. Sear the salmon flesh-side-down for 5 minutes undisturbed, until it's deeply golden. Carefully flip and cook for another 1-2 minutes, or until the internal temperature reaches 125 and the salmon begins to flake. Cook time may vary based on thickness of your salmon. Transfer the cooked salmon to a clean plate.
1 lb skin-on salmon filets, 2 Tablespoons unsalted butter, 1 teaspoon kosher salt
Make the pesto sauce: Pour 1/3 cup of the pasta cooking water (or dry white wine) in the pan, scraping any brown bits form the bottom of the pan. Stir in the pesto and allow it to simmer over medium heat for 1-2 minutes. Stir in the cream and lemon juice and whisk to combine. Simmer the sauce over medium-low heat to warm and thicken for 5-6 minutes.
1/3 cup pasta cooking water, 1/2 cup pesto, 1/4 cup heavy cream, 1 teaspoon fresh lemon juice
Toss the pasta: Add the cooked pasta to the pesto sauce and toss gently to coat. Top the pasta with the raw asparagus then cover and steam the asparagus for 3-4 minutes over medium heat. Open the lid and stir to combine.
1 lb asparagus
Finish and serve: While the asparagus cooks, remove the skin from the salmon and use a spoon or fork to break up the salmon into chunks. Top the pasta with the cooked salmon and toss gently to coat the salmon with the creamy pesto sauce. Serve with grated parmesan cheese, a few spoonfuls of pesto, and fresh basil.