Cook the penne pasta according to package instructions until al dente. Drain and set aside, reserving 1/2 cup of pasta water.

In a large skillet, heat the olive oil over medium heat. Season the salmon fillets with salt and pepper, then add them to the skillet. Cook for about 4-5 minutes on each side, or until the salmon is cooked through and flakes easily. Remove the salmon from the skillet and set aside.

In the same skillet, add the minced garlic and sauté for about 30 seconds until fragrant.

Pour in the diced tomatoes (with their juice), heavy cream, and Italian seasoning. Stir to combine and bring to a simmer.

Add the fresh spinach to the sauce and cook until wilted, about 2-3 minutes.

Flake the cooked salmon into bite-sized pieces and return it to the skillet. Add the cooked penne pasta and toss everything together. If the sauce is too thick, add some reserved pasta water to reach desired consistency.

Stir in the grated Parmesan cheese and mix until melted and creamy. Taste and adjust seasoning if needed.

Serve hot, garnished with fresh basil if desired.