Ingredients
Method
- Toast the sourdough and stir the mayonnaise with horseradish.
- Spread the mixture on one side of every toast slice.
- Divide half the roast beef, cheddar and arugula over two slices and top with two more toast slices spread-side up.
- Add the remaining beef and drained pickled onions, then close with the last toast spread-side down.
- Secure with toothpicks, quarter each sandwich and serve.