Prepare rice according to package directions; set aside.
Combine pineapple and next 3 ingredients in a bowl, and set aside.
Peel shrimp, and devein, if desired. Sauté shrimp in 1 tablespoon hot oil in a large skillet 3 minutes. Remove shrimp from skillet, and set aside.
Heat remaining 2 tablespoons oil in skillet over medium heat; add garlic, and sauté 2 minutes or until golden brown. Stir in rice, fish sauce, soy sauce, and sugar. Cook, stirring constantly, until thoroughly heated.
Fold in pineapple mixture and shrimp, and cook until thoroughly heated. Garnish, if desired.