Preheat an oven to 190°C.
Place the new potatoes into a pot of boiling salted water and cook for 10-12 minutes until cooked through. Remove and cool to room temperature.
Cook the Sealord Three Seed Crumb Hoki fillets as per packet instructions.
Place the walnuts onto a baking tray and toast for 10 minutes in the oven. Keep an eye on them so they don't burn!
Mix the red onion and white wine vinegar in a small bowl.
Gently fold the pesto through the potatoes.
Place the watercress, new potatoes, red onions and crumbled cheese onto a platter. Top with a piece of warm Three Seed hoki.
Sprinkle with the walnuts and squeeze over lemon.
Season with salt and pepper to taste.