Mix well mayonnaise, mustard and cream and season with
salt and pepper.
Halve avocado, remove seeds, peel and cut into thin slices. Peel onion
and cut tomatoes into slices.
Heat 3 tbsp. oil and fry salmon.
Cover the bottom of the buns with mustard cream and with lettuce leaves.
Upon avocados, tomatos and onions. Place salmon fillets upon and finish
with mustard sauce.