Melt butter in 3 qt. pot. Saute onion, celery, pepper & garlic until onion is wilted, 3-5 min. Add tomato paste, stirring constantly 3 min. over low heat. Add 1 1/2 cups of water & sugar. Season to taste with salt, pepper, & cayenne. Cook uncovered over medium-low
heat 20 min, stirring occasionally.
Add shrimp. Cook until shrimp are pink and cooked through. 3-5 min.
Dissolve cornstarch in 1/2 cup water and add. Cook another 2 min. Mix ingredients with cooked rice. Add green onion and parsley. Mix again.