Bring a large pot of heavily salted water to a rolling boil. Add the penne and cook according to package directions until al dente. Reserve 1 cup (240ml) of pasta water, then drain the pasta.

While pasta cooks, pat salmon chunks dry and season with salt and pepper. Heat olive oil in a large skillet over medium-high heat. Sear salmon for 2-3 minutes per side until a golden-brown crust forms. Remove from skillet and set aside.

Reduce heat to medium, add butter to the skillet. Once melted, add minced garlic and sauté for 30-60 seconds until fragrant. Pour in broth, scraping up any browned bits. Whisk in heavy cream and simmer for 2-3 minutes to thicken.

Stir in the grated Parmesan cheese until melted and smooth. Add the spinach and stir until just wilted. Season with salt and pepper. Return the cooked penne and seared salmon to the skillet. Gently fold to combine. If needed, thin the sauce with a splash of reserved pasta water.

Serve immediately, garnished with more Parmesan, coarsely cracked black pepper, and chopped fresh parsley.