Trim tough outer leaves from fennel; remove and discard stalks. Cut bulb in half vertically, discarding core. Cut each half crosswise into 1/4-inch-thick slices. Heat oil in a nonstick skillet over medium-high heat. Add the fennel and onion, and cook, stirring constantly, 7-10 minutes or until browned. Reduce heat to medium; add shrimp and next 5 ingredients (shrimp through pepper), stirring constantly until thoroughly heated.