Start by ensuring your red snapper fillets are thoroughly cleaned and dried.

In a large skillet over medium heat, warm the olive oil until shimmering.

Add the chopped onions, green bell pepper, and celery into the skillet. Sauté until they soften and turn fragrant, about 5 minutes.

Stir in the minced garlic and cook for an additional minute, being careful not to let it brown.

Sprinkle the flour over the vegetable mixture, stirring continuously to create a roux. Cook for another minute.

Gradually add the chicken broth while whisking to avoid lumps. Bring the mixture to a gentle simmer.

Mix in the heavy cream, Creole seasoning, Worcestershire sauce, cayenne pepper (if using), and season with salt and black pepper. Let it simmer until slightly thickened, about 5-7 minutes.

In a separate pan or after removing the sauce, melt the butter over medium heat.

Add the red snapper fillets, cooking for about 4-5 minutes per side, depending on thickness, until the fish is opaque and flakes easily.

Plate the cooked red snapper and generously spoon the creamy Creole sauce over the fillets.

Garnish with fresh parsley and serve over a bed of cooked rice.