##peel and chop the onion## Wash and peel the beetroot and slice or cut it into wafer-thin slices. (Attention! Dye strongly - it is best to put on disposable gloves).
Preheat oven (electric cooker: 175°C/circulating air: 150°C/gas: level 2). Heat oil in a pan. Steam onion and beetroot for about 2 minutes, turning them over. Sprinkle with 1 tbsp. sugar and caramelise while turning.
##Add vinegar##, simmer for 2-3 minutes. Season with salt and pepper. Take out beetroot with the stock and let it cool down.
Heat salmon on baking paper in the oven for 3-4 minutes. Clean, wash and dry lamb's lettuce. Fold into the beetroot salad. ##Peel and grate horseradish and mix with lemon juice.
Cut the salmon into slices. Arrange on the salad with horseradish. Goes well with baguette.