1In 1-quart saucepan, heat 1 1/2 cups water to boiling over high heat. Stir in rice; return to boiling. Reduce heat to low; cover and simmer 5 minutes. Remove from heat. Let stand covered 5 minutes; fluff with fork and let cool slightly.
2Meanwhile, in small bowl, mix sauce ingredients until smooth; set aside.
3In 12-inch nonstick skillet, heat oil over medium-high heat. Add onions and garlic; cook 1 minute, stirring frequently. Add bell peppers; cook about 5 minutes, stirring frequently, until softened. Add shrimp and tomatoes; cook 3 to 5 minutes, stirring frequently, until shrimp are pink and peppers are crisp-tender.
4Stir sauce into shrimp mixture. Heat to boiling; cook and stir until sauce is thickened. Serve over rice.