Wash the potatoes and cook in water for 15-20 minutes. Quench cold and peel. Clean, wash and chop the beans. Peel onion and chop finely. Heat 10 g butter in a pot and fry the onion in it.
Add the beans and steam briefly. Season with salt. Add broth and cook for 12-15 minutes at low heat. Wash the savory, dab dry, chop coarsely and add to the beans shortly before the end of the cooking time.
Wash the salmon and dab dry. Line a gratin dish with parchment paper and coat with butter. Put salmon in it and sprinkle with lemon juice. Season with salt and pepper and cook in a preheated oven (electric cooker: 200 °C/ gas: level 3) for about 20 minutes.
In the meantime, crumble the bread and after about 10 minutes cooking time, sprinkle it over the salmon and place the remaining butter as flakes on top. For the sauce, wash the parsley and dill, dab dry, and pluck leaves or flags from the stalk.
Add herbs and horseradish to the mayonnaise. Add milk and puree with a blender. Heat the oil in a pan and fry the potatoes all around until golden brown. Season with salt. Arrange salmon, beans and roast potatoes together with the herb mayonnaise and serve garnished with dill, dill flowers and lemon slices as desired.