Cook the rice in a small pot in salted water for about 20 minutes. Then drain and drain well. Wash the beans and cook in boiling salted water for 16-18 minutes. Drain. Wash radishes and cut into slices.
Wash and chop the spring onions. Dill wash, pluck and chop. Mix yoghurt, mayonnaise and horseradish until smooth. Stir in dill. Season to taste. Mix rice, radish, spring onion, beans and sauce.
Cut the trout filet into pieces. Arrange and garnish everything.