Melt 2 Tablespoons Butter In A Small Nonstick Skillet Over Medium Heat. Cook The Garlic In The Butter Until Softened, About 1 Minute. Stir In The Zucchini And The Onion; Cover, Cook For 2 Minutes. Mix The Chicken And The Remaining 1 Tablespoon Butter Into The Skillet; Cover. Stirring Occasionally, Cook Until Chicken Is No Longer Pink, About 5 Minutes.