Amount per serving
Combine Knorr® Vegetable Bouillon Cube and water in small microwave-safe bowl and cook at HIGH 1 minute. Stir until dissolved; set aside.
Heat Oil in large nonstick skillet over medium-high heat and cook Brussels sprouts and onion, stirring frequently, until seared, about 6 minutes. Stir in Bouillon mixture, cover and cook, stirring occasionally, until Brussels sprouts are tender, about 3 minutes.
Stir in balsamic vinegar. Serve topped with feta cheese.