Steps
- Preheat oven to 200°C. Place the grated potato, onion, and carrot in a colander, and use your hands to squeeze out as much liquid as possible. Transfer to a large bowl, then add the sweet potato and olive oil. Stir to combine and season with salt and pepper.
- Spray a 30cm x 40cm baking tray with olive oil spray. Spread the vegetable mixture evenly over the prepared tray and spray the top with olive oil. Bake for 30-35 minutes, or until the rosti is golden and edges are crisp.
- Meanwhile, in a small bowl, combine crème fraîche (or sour cream), Greek yoghurt, lime rind, and lime juice. Season with salt and pepper.
- In a medium bowl, toss together the watercress, radish, and capers to create the salad.
- Use a spatula to break the rosti into large pieces and arrange them on a serving platter. Top with smoked trout, the watercress salad, and dollops of the crème fraîche mixture. Season to taste and serve.