Combine 1 1/2 cups water, rice, and next 7 ingredients in a large saucepan. Bring to a boil; cover, reduce heat, and simmer 30 to 35 minutes or until rice is tender and liquid is absorbed.
Heat oil in a Dutch oven over medium-high heat. Add onion and garlic; saute until tender. Add remaining 3/4 cup water, tomato paste, and next 3 ingredients, stirring well. Bring to a boil; cover, reduce heat, and simmer 25 minutes, stirring occasionally.
Spoon rice mixture evenly into individual serving bowls, making a well in each serving with the back of a spoon. Spoon bean mixture evenly over rice, and top each serving with 1 tablespoon sour cream.