Peel and clean the cucumbers, cut them in half lengthwise. Remove seeds, dice cucumber. Peel and finely dice onions. Peel, wash and cut potatoes into small pieces. Heat the fat in a pot.
Steam cucumbers, onions and potatoes in the fat until transparent. Pour in broth, bring to the boil and simmer for about 15 minutes. In the meantime roast almond flakes in a pan without fat, take them out. Rinse lime with hot water and grate dry.
Peel the lime zest with the zest ripper. Halve the lime, squeeze the juice. Remove soup from the stove and puree finely with a hand blender. Season with salt, pepper and nutmeg. Season to taste with lime zests, juice and horseradish.
Cut the trout filets into pieces. Arrange soup with trout fillets in plates. Garnish with cress and almonds. Serve with baguette.