Ingredients

3 tablespoons butter

2 tablespoons extra-virgin olive oil

1 large onion, coarsely chopped (about 2 1/2 cups)

2 medium rutabagas, peeled, cut into 1/3-inch cubes (about 3 cups)

2 medium turnips, peeled, cut into 1/3-inch cubes (about 2 1/2 cups)

2 large carrots, peeled, cut into 1/3-inch cubes (about 2 cups)

2 large parsnips, peeled, cut into 1/3-inch cubes (about 1 1/2 cups)

2 1/2 cups diced celery (about 4 stalks)

2 (7.25-ounce) jars whole roasted peeled chestnuts, halved

6 garlic cloves, minced

2 tablespoons chopped fresh thyme

Preparation

Melt butter with oil in very large pot over medium-high heat. Add onion; sauté 5 minutes. Add rutabagas and next 4 ingredients; sauté until vegetables are caramelized and tender, stirring often, about 30 minutes. Stir in chestnuts, garlic, and thyme; sauté 5 minutes. Season generously with salt and pepper. Do ahead Can be made 1 day ahead. Cover and chill. Rewarm over medium heat, stirring frequently, until heated through before serving.