1. Separate stems from leaves of chard. Slice stems into 2-inch pieces; set leaves aside. In a large saucepan, cook chard stems in boiling salted water 2 minutes. Add chard leaves and cook 3 minutes longer. Drain well.
2. In a large frying pan, heat oil over medium heat. Add onion and cook 2 to 3 minutes, or until softened. Add garlic and cook 1 minute longer. Add Swiss chard, chick-peas, tomatoes, and 1 cup water. Partially cover and simmer 12 minutes, or until flavors blend and excess liquid evaporates. Season with salt and pepper.