Wash the dill and chop finely. Peel onion and chop finely. Mix cream cheese, dill, onion and salmon cream until smooth. Season with pepper, lemon juice and horseradish. Cut the bagel open.
Wash the salad and dab dry. Cover the lower half of the roll with a slice of salmon and a salad leaf. Spread cream on top. Place the lid of the roll on top. Add caviar as desired.