Slice zucchini and squash in thin rounds. Mix with garlic, oregano, and pepper, and place in a steamer basket over boiling water. Cover and steam 2 minutes or until just tender. Remove from basket to serving bowl and toss with oil. Food Exchange per serving: 1 VEGETABLE EXCHANGE; CAL: 34; CHO: 0mg; CAR: 6g; SOD: 3g; FAT: 1g;