1. Prepare beef top round steak with unseasoned meat tenderizer as label directs. Cut steak lengthwise in half; cut each half crosswise into 1/4-inch-thick slices.
2. In 12-inch skillet over high heat, in hot salad oil, cook meat, stirring constantly, until browned on all sides, about 2 minutes. With slotted spoon, remove meat to medium-sized bowl.
3. In drippings remaining in skillet over medium heat, cook onion, green pepper, and paprika, stirring frequently, until vegetables are tender. Return meat to skillet. Add half-and-half, sherry, salt, and pepper; heat mixture to boiling. Reduce heat to low; cover and simmer 15 minutes, stirring occasionally, until meat is fork-tender.
4. In cup, stir water and flour until blended. Gradually stir flour mixture into liquid in skillet; cook over medium heat, stirring constantly, until sauce thickens slightly.