Perch with Nut Topping on Autumnal Vegetables

Preheat the oven to 200°C (approximately 400°F).

Toast the nuts in a dry non-stick pan, stirring. Remove to a bowl and allow to cool. Peel the pumpkin and cut the flesh into cubes. Rinse scallions and halve or quarter depending on length. Rinse celery and cut into 10 cm (approximately 4-inch) long pieces. Peel potatoes, rinse and cut in half. Mix the vegetables in a bowl with the oil and season with salt, pepper and lemon juice. Place vegetables in an oven-proof dish (or on a baking sheet) and roast the in the oven (middle shelf) for about 30 minutes, turning occasionally. Remove and set aside.

Finely grind the nuts. Mix the butter with the herbs, nuts, salt and pepper to taste, lemon zest and nutmeg. Place mixture in a piping bag with a 5 mm (approximately 1/4-inch) tip. Increase oven temperature to 220°C (approximately 425°F). Season the fish fillets with salt and pepper and put on a baking sheet. Pipe the nut butter onto the fish fillets and bake in the oven until the nut mixture has a golden brown crust, about 10 minutes.