A hearty dish for early spring that's at once briny and herbaceous, rich and bracing. Fettuccine noodles are tossed with delicate roasted spring onions, capers, herbs, tinned sardines, and buttery panko for a meal that's deeply satisfying. This dish is layered and can easily be adjusted to suit your tastes or the season. Keep a cup of pasta water on hand to bind it all together. To offset all the salty richness, serve alongside a lemony salad of bitter greens.