Combine the beef, rub, and vegetable oil in a bowl and toss to coat.
Brown the beef evenly in a large skillet over medium-high heat for 4 to 6 minutes. Do not crowd the beef in the skillet. Transfer the beef to a large bowl and add the onion, parsley, and green onions. Set aside to cool.
To make the dressing, combine the egg, horseradish, garlic, lemon juice, Worcestershire, and Tabasco in a food processor. Process until smooth. With the motor running, pour the olive oil through the feed tube in a steady stream. The mixture will thicken. Add the salt and pepper and pulse once or twice to blend.
Add the dressing to the beef mixture and toss to coat thoroughly. Cover and refrigerate for at least 1 hour before serving. Serve chilled.
Yield: 6 servings