Food & Cooking Recipes Main Dish Recipes Casserole Recipes Green-Bean Casserole with Chestnuts and Buttered Breadcrumbs Be the first to rate & review! By Martha Stewart Test Kitchen Martha Stewart Test Kitchen The recipes developed by our test kitchen team have undergone a rigorous process of development and testing, ensuring that every element is optimal, from ingredient amounts to method and cooking time. This process includes triple-testing recipes to ensure they meet our high standards. The many stellar cooks and food editors who have been part of our team include Sarah Carey, Lucinda Scala Quinn, Jennifer Aaronson, Shira Bocar, Anna Kovel, Greg Lofts, Riley Wofford, Lauren Tyrell, and Lindsay Leopold. Editorial Guidelines Updated on October 14, 2019 Print Rate It Share Share Tweet Pin Email Photo: Con Poulos Prep Time: 1 hr Total Time: 2 hrs 10 mins Yield: 10 to 12 Serves This holiday season, give the humble green bean casserole an elegant makeover. This recipe keeps it easy, creamy, and as delicious as always but using fresh green beans makes a world of difference to the texture of the finished dish, and the additions of seasonal roasted chestnuts and mixed wild mushrooms make it a classy, crowd-pleasing side dish. Ingredients 12 tablespoons unsalted butter, plus more for baking dish Kosher salt and freshly ground pepper 2 pounds green beans, trimmed 3 cups coarse fresh breadcrumbs 6 ounces peeled roasted chestnuts, coarsely chopped (1 ¼ cups) ½ cup coarsely chopped fresh parsley leaves 1 ½ cups whole milk 1 ½ cups heavy cream 1 clove garlic, minced 10 ounces mixed mushrooms, such as cremini, oyster, and trumpet, sliced (4 cups); plus 2 trumpet mushrooms, thinly sliced lengthwise (optional) 1 onion, finely chopped (2 cups) ¼ cup unbleached all-purpose flour Pinch of freshly grated nutmeg Extra-virgin olive oil, for tossing (optional) Directions Preheat oven to 350°F. Generously brush a 3-quart baking dish with butter. Prepare a bowl of salted ice water. Cook green beans in a large pot of generously salted boiling water until crisp-tender and dark green, 3 to 4 minutes. Drain; immediately transfer to ice water until thoroughly chilled. Drain and pat dry. Halve beans on the bias and transfer to prepared dish. In a bowl, toss breadcrumbs with chestnuts to combine. Melt 6 tablespoons butter; drizzle evenly over breadcrumb mixture, tossing until evenly absorbed. Toss in parsley; season with salt and pepper. In a small saucepan, heat milk and cream over medium-low until scalding and bubbles emerge along edges of pan. Remove from heat; cover to keep warm. Sprinkle garlic with a pinch of salt; mash into a paste with the side of a knife. In a large straight-sided skillet, melt remaining 6 tablespoons butter over medium heat. Add mixed mushrooms; season with salt. Cook, stirring occasionally, until tender and beginning to brown, 15 to 18 minutes. Add onion, season with salt, and cook, stirring often, until onion is translucent but not browning, about 5 minutes. Stir in garlic; cook 1 minute more. Sprinkle flour evenly over mixture and cook, stirring, 2 minutes. Slowly add milk mixture, stirring, and bring to a simmer. Cook until thickened slightly, about 3 minutes. Stir in nutmeg; season with salt and pepper. Pour mixture evenly over green beans in dish. Sprinkle breadcrumb mixture evenly over top. Bake until bubbly along edges and crisp golden brown on top, about 30 minutes. Meanwhile, toss sliced trumpet mushrooms with enough oil to lightly coat, season with salt and pepper, and arrange in a single layer on a rimmed baking sheet. Roast until tender and golden brown along edges, about 30 minutes. Top casserole with roasted mushrooms and serve warm. Rate it Print