Place sauce in a blender or food processor; pureé finely. Transfer to a large sauté pan over medium-high heat and bring to a simmer. Add the oysters and cook, stirring, until oysters are plump and edges are beginning to curl, just a few minutes. Remove oysters from sauce and set aside; keep warm.

Add cooked pasta to hot sauce along with green onions and parsley; toss to coat thoroughly. Divide among 6 serving bowls; add oysters back to pan and sauté briefly, then divide among servings. Sprinkle with Parmesan, serve with hot buttered French bread.

Creole Sauce

To prepare the sauce, place all ingredients in a large stock pot over medium-high heat. Bring to a simmer, reduce heat, cover, and simmer, stirring from time to time, until the acidity of the tomatoes is gone and the onions are very soft, 2 to 3 hours. Add additional water as necessary; sauce should be thick but still saucy. Remove and discard bay leaves.

This makes about 4 1/2 gallons; Sauce will keep, refrigerated, for up to a week; may be frozen for up to 6 months.