- 1 1/2 pounds beef tenderloin or sirloin, cut into 1-inch chunks
- 1 tablespoon Rustic Rub 
- 1 tablespoon vegetable oil
- 1 large yellow onion, cut in half and thinly sliced
- 3 tablespoons chopped parsley
- 3 tablespoons chopped green onions
- 1 egg
- 1/2 cup freshly grated horseradish or 1 teaspoon prepared horseradish
- 1 tablespoon chopped garlic
- 1 tablespoon fresh lemon juice
- 1/2 teaspoon Worcestershire sauce
- 1/2 teaspoon Tabasco sauce
- 1 1/4 cups olive oil
- 3/4 teaspoon salt
- 1/4 teaspoon freshly ground black pepper
- 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.