In a medium saucepan, bring 2 cups water to a boil. Stir in the long-grain rice, reduce heat to low, cover, and simmer for about 20 minutes, or until the water is fully absorbed.
Add the chopped onion and minced garlic; cook for about 3 minutes until softened. Stir in the chopped red and green bell peppers and cook for 5 minutes until they are tender.
When the rice is done, gently stir it into the skillet with the sautéed vegetables. Taste and adjust the seasoning if needed.