Preheat oven to 400 degrees F.

If using parsnips, quarter lengthwise and remove the woody core before cutting into 1-inch pieces. Whisk cider, brown sugar, 1/2 teaspoon salt and pepper in a 9-by-13-inch baking dish until the sugar is dissolved. Add root vegetables and toss to coat. Cover the baking dish with foil.

Bake for 20 minutes. Uncover and stir the vegetables. Continue cooking, uncovered, stirring every 20 minutes or so, until the vegetables are glazed and tender, about 1 hour more.

Meanwhile, place walnuts in a small skillet and cook over medium-low heat, stirring constantly, until fragrant and lightly browned, 2 to 6 minutes. Remove from the heat and add butter, cinnamon and a pinch of salt. Stir until the butter melts and the nuts are coated. Spread out on a plate to cool slightly.

Transfer the vegetables to a serving dish and sprinkle with the cinnamon walnuts.

Tip: Beets, carrots and parsnips are easily peeled with a vegetable peeler, but for tougher-skinned roots like celeriac, rutabaga and turnips, removing the peel with a knife can be easier. Cut off one end of the root to create a flat surface to keep it steady on the cutting board. Follow the contour of the vegetable with your knife. If you use a vegetable peeler on the tougher roots, peel around each vegetable at least three times to ensure all the fibrous skin has been removed.