Saute onion, garlic, green pepper and celery in butter or bacon grease in large heavy pan over moderate heat for 12 minutes or until onion is golden brown.
Add parsley, ham, thyme and bay leaves.
Fry, stirring often for another 5 minutes.
Add pepper sauce, salt tomatoes, tomato sauce and the water.
Simmer for five minutes.
Add rice, adjusting heat so liquid boils very gently, cover and cook for 30 minutes.
Add shrimp to float on top (don't mix in- it's intended to steam on the top), re-cover and simmer an additional 10 minutes (depends on size of shrimp) or until shrimp are cooked, rice is tender and liquid is absorbed.