Preheat your oven to 400°F (200°C).
In a large skillet, heat the olive oil over medium heat. Add the chopped onion and sauté until translucent, about 5 minutes.
Stir in the minced garlic and cook for an additional minute until fragrant.
Add the chopped roasted red peppers, heavy cream, oregano, smoked paprika, salt, and pepper. Bring the mixture to a gentle simmer and cook for 5-7 minutes, stirring occasionally, until slightly thickened.
While the sauce is simmering, season the salmon fillets with salt and pepper. Place them in a baking dish and pour the roasted pepper sauce over the top.
Bake in the preheated oven for 15-20 minutes, or until the salmon is cooked through and flakes easily with a fork.
Remove from the oven and let it rest for a few minutes. Garnish with fresh basil or parsley if desired before serving.