Pat the salmon fillets dry with paper towels. In a small bowl combine smoked paprika, garlic powder, Italian seasoning, salt, oregano, black pepper, and red pepper flakes; rub the spice mix evenly over both sides of the salmon.
Heat the olive oil in a large heavy-duty skillet over medium-high heat. When hot, add the salmon and cook about 4 minutes per side until seared and nearly cooked through. Transfer the salmon to a plate and set aside.
Reduce heat to medium and add the butter to the same skillet. Add the diced onion and cook 2–3 minutes until translucent and lightly golden.
Add the chopped garlic and cook about 30 seconds until fragrant, stirring constantly to avoid burning.
Pour in the heavy whipping cream and chicken broth, then stir in the sliced sun-dried tomatoes and shredded Parmesan until the cheese melts and the sauce is combined; taste and adjust salt if needed.
Return the seared salmon to the skillet, spoon some sauce over the fillets, and simmer gently 2–3 minutes more until the salmon is cooked through to your liking.
Turn off the heat, garnish with fresh basil, and optionally finish with a squeeze of lemon juice before serving.
