In a medium sized pan, melt butter over medium heat. Thoroughly stir in flour making sure there are no lumps to begin the roux. Allow the roux to develop, stirring frequently for about 9-10 minutes (until dark but make sure it doesn't burn).
Next stir in onions, celery and green peppers and cook for a few minutes until tender, frequently stirring.
Pour in chicken stock and white wine then add tomato paste and diced tomatoes and whisk together everything.
Season with creole seasoning, garlic powder, cayenne pepper, worcestershire sauce, lemon juice and hot sauce.
Allow the mixture to cook for 10-12 minutes over medium heat to come together and begin to thicken then add the shrimp and salt and pepper to taste. Cook for another 10 minutes on a lower heat with the lid on.
Stir in heavy whipping cream then cook for 2-3 more minutes until thickened. Serve over rice and garnish with chopped parsley and green onion.
Allow the roux to develop, stirring frequently for about 9-10 minutes (until dark but make sure it doesn't burn).