Cut the carrots and parsnips in half lengthwise and again crosswise.
Cut the turnips halves into 1-inch wedges.
Place the carrots, parsnips, turnips, Brussels sprouts and shallots in a large bowl. Drizzle with tablespoons of the oil. Toss to combine.
Line a sheet pan with foil and arrange the vegetables in one layer on top of the foil, sprinkle with salt and ground black pepper.
Place the sheet pan in the oven. Roast the vegetables for 50 minutes or until tender and nicely browned.
Remove sheet pan from the oven. Transfer the vegetables to a large platter; cover to keep warm
The Gremolata
Grate the yellow peel (the zest) of the lemon with a grater or a microplane until you have accumulated a tablespoon. Avoid the bitter white part (the pith).
Cut the lemon in half. Squeeze the juice into a bowl and remove the seeds.
Place the walnuts in a jar chopper and coarsely chop.
Transfer the walnuts to a bowl. Add all of the cheese, parsley, garlic and lemon zest, plus 1 tablespoon of lemon juice and 1 tablespoon of oil. Stir to combine.
Serve It Up
Spread the gremolata evenly over the warm vegetables and gently toss to coat.
Place all of the vegetables in a large mixing bowl. Season with garlic, salt, black pepper, allspice, and chili flakes. Drizzle with olive oil. Toss the mixture thoroughly to combine.
Line a sheet pan with foil.
Turn seasoned vegetable mixture on to sheet pan. Spread the vegetables out on the pan.
Place pan in oven. Roast for 7 minutes. Remove from oven.
Roast Fish
Cut fish fillets into 2 inch pieces.
Season fish pieces with salt and black pepper.
Place the fish pieces on top of the vegetables.
Return fish and vegetables to the oven. Roast for 8 minutes.
