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Green bean casserole is a mealtime favorite, but this one has a slight twist, in that the onions are less crispy and more caramelized: offering a unique, new flavor to the meal. This casserole is a delicious dish to make that is the perfect accompaniment to any main course for any big dinners coming up, switch up your routine and try this updated version of the green bean casserole! The results include delightfully fresh green beans in a thick and creamy sauce (if it can be described as thick and creamy, it’s all right with us) and beautifully caramelized onions that complement everything exquisitely. What’s not to love?

Onion Mushroom Green Bean Casserole

Serves 6-8


  • 2 pounds green beans, ends removed, halved
  • 6 oz. cremini mushrooms, sliced
  • 1 large yellow onion, sliced
  • 1 egg, lightly beaten
  • 1 cup crème fraiche (or heavy cream)
  • 1 cup Parmesan cheese, grated
  • 3 tablespoons butter, divided
  • 1/4 teaspoon nutmeg
  • kosher salt and freshly ground pepper, to taste


  1. Preheat oven to 375º F and bring a pot of water up to a boil.
  2. Heat 1 tablespoon butter in a large pan over medium-low heat. Once melted, add onion slices and saute until soft and golden, stirring frequently. 20-25 minutes. Reduce heat further if onions are getting crispy. Set aside.
  3. In a separate pan, heat remaining butter over high heat and add mushrooms. Cook for 3 minutes, stirring frequently, until mushrooms are slightly browned. Season with salt and pepper and set aside.
  4. Blanch green beans in boiling water for 5 minutes. Remove and immediately set in an ice bath to stop them from cooking more.
  5. Beat the egg into the crème fraiche and stir in Parmesan, nutmeg and pinch of salt and pepper.
  6. Add mushrooms and green beans (patted dry with a paper towel) to the crème fraiche and toss to coat thoroughly.
  7. Pour mixture into casserole dish (9×13-inch) and set caramelized onions around the edge as a border. Bake for 30 minutes, or until onions are slightly crisped.
  8. Remove from oven, let cool 5 minutes and serve hot.

Recipe adapted from Not Eating Out In New York

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