Place whole blue potatoes in a pot of cold salted water. Bring to a boil, lower heat to medium and cook until tender, about 15 minutes depending on their size.

Bring another large pot of water to a boil.

Meanwhile, separate the Romanesco florets and wash them.

Cook the Romanesco florets in boiling water for about 10 minutes. Drain and rinse with cold water.

Let potatoes and Romanesco cool down to lukewarm.

Combine all the ingredients of the dressing.

Peel potatoes and slice. Place potatoes and florets in a bowl, sprinkle with fresh dill, pour dressing and mix well (but gently).

Serve in salad plates or bowl, adding small pieces of smoked salmon on top, and some more dill if desired. Drizzle lightly with lemon.