Bring a large pot of water to a boil, add the dried garbanzo beans, cover, and cook for 30 minutes, or until just tender. Drain, rinse with cold water, and set aside. Heat the olive oil in a saucepan over low heat. Add the onion, scallions, and thyme and cook, covered, about 25 minutes, or until the onion is tender. Add the bell pepper and cook for 5 minutes more. Add the raisins and garbanzos, and cook for 5 minutes more, stirring occasionally. (Don’t overcook the garbanzos, or they will become mushy.) Season with salt, transfer to a bowl, and stir in the vinegar. Set aside to cool. Cover and refrigerate for at least 24 hours. Allow to come to room temperature before serving.