Bring the wine to the boil in a small saucepan and boil for 5 minutes until syrupy and reduced by half. Add the crème fraîche, a squeeze of lemon juice and most of the dill. Season, then stir until mixed through.
Meanwhile, cook the lasagne sheets in a large saucepan of salted boiling water for 3–5 minutes or until soft, then drain well. Shave the courgettes into long thin strips using a vegetable peeler.
Cut each lasagne sheet into large irregular shapes and place in a bowl. Break the salmon into large chunks.
Arrange the salmon and pasta on serving plates with the courgette ribbons. Drizzle over the sauce and serve sprinkled with the spring onions and the remaining dill.