Best Red Snapper with Creamy Creole Sauce

Ingredients:

For the Red Snapper:

4 red snapper fillets
2 tablespoons olive oil
Salt and pepper, to taste
1 tablespoon Cajun seasoning
For the Creamy Creole Sauce:

1 tablespoon butter
1 small onion, finely chopped
1/2 green bell pepper, finely chopped
1 celery stalk, finely chopped
2 cloves garlic, minced
1 tablespoon all-purpose flour
1 cup chicken or seafood stock
1/2 cup heavy cream
1 tablespoon tomato paste
1 teaspoon Creole seasoning
1/2 teaspoon smoked paprika
1/4 teaspoon cayenne pepper (optional for extra heat)
Salt and pepper, to taste
1 tablespoon fresh parsley, chopped