Mix vinegar and mustard with a whisk in a bowl. Slowly add the oil, stirring constantly. Wash the parsley and chives, dab dry, chop finely and add to the vinaigrette. Season to taste with salt and pepper
Defrost the beans in a sieve. Wash and clean broccoli and spring onions and dab dry. Cut spring onions into fine strips. Halve avocados, remove seeds, cut flesh halves into 8 slices each
Blanch broccoli and beans briefly in boiling water for about 4 minutes, drain and drain. Roast sunflower seeds in a pan without fat, remove from heat and let cool off
Arrange broccoli, beans, spring onions and avocado pieces on plates, drizzle vinaigrette over them, sprinkle with pepper. Spread cress and sunflower seeds on top