Broil green pepper and jalapeno 4 in. from the heat until skins blister, about 4 minutes. With tongs, rotate peppers a quarter turn. Broil and rotate until all sides are blistered and blackened. Immediately place peppers in a bowl; cover and let stand for 15 minutes. Peel off and discard charred skin. Remove stems and seeds; chop peppers.
Place 1 cup of water in a food processor. Add the peppers, spinach, cilantro and onions; cover and process until smooth.
In a large skillet, saute rice in oil until golden brown. Stir in the spinach puree, salt and remaining water. Bring to a boil. Reduce heat; cover and simmer for 15 minutes. Remove from the heat. Let stand for 10 minutes before serving.