Ingredients:

  • 3 large shallots, thinly sliced
  • 2 Tablespoons all-purpose flour (for shallot dusting)
  • ½ teaspoon salt (for shallots)
  • 2 cups neutral oil (e.g., Canola, Grapeseed), for frying
  • 5 pounds fresh green beans (Haricot Verts preferred), trimmed
  • 1 Tablespoon salt (for blanching water)
  • 4 Tablespoons unsalted butter
  • 10 ounces Cremini mushrooms, finely sliced
  • 2 cloves garlic, minced
  • 4 Tablespoons all-purpose flour (for roux)
  • 5 cups chicken or vegetable stock, low-sodium
  • 1 cup heavy cream (Double Cream)
  • ½ cup whole milk
  • 1 teaspoon Worcestershire sauce
  • ½ teaspoon freshly ground black pepper
  • Salt, to taste

Instructions:

  1. Prepare and Fry the Shallot Topping: Toss the thinly sliced shallots with the 2 Tablespoons of flour and ½ teaspoon of salt until lightly coated. Pour the neutral oil into a large skillet and heat over medium-high heat until it reaches 325°F (160°C). Working in batches to avoid overcrowding, fry the shallots until deep golden brown and crispy (about 3-5 minutes per batch). Immediately transfer the crispy shallots using a slotted spoon to a wire rack lined with paper towels. Season lightly with a final pinch of salt immediately.
  2. Blanch the Green Beans: Bring a large pot of salted water (using 1 Tablespoon salt) to a rolling boil. Add the trimmed green beans and cook for exactly 3-4 minutes until they are bright green and tender-crisp (al dente). Immediately drain the beans and plunge them into a large bowl of ice water to stop the cooking process. Drain well and set aside.
  3. Make the Mushroom Cream Sauce: Melt the butter in a large saucepan over medium heat. Add the sliced mushrooms and sauté until the moisture evaporates and the mushrooms are deeply browned (about 5-7 minutes). Add the minced garlic and cook for 1 minute until fragrant. Sprinkle the 4 Tablespoons of flour over the mixture, stirring constantly for 2 minutes to cook out the raw flour taste (forming the roux base). Gradually whisk in the stock until smooth, then whisk in the milk and heavy cream. Bring the mixture to a gentle simmer, stirring constantly until the sauce thickens to coat the back of a spoon. Remove from the heat and stir in the Worcestershire sauce, pepper, and salt. Taste and adjust seasoning as needed.
  4. Assemble and Bake the Casserole: Preheat oven to 375°F (190°C). Gently fold the blanched green beans into the creamy mushroom sauce until fully coated. Pour the mixture into the prepared 9 x 13 inch casserole dish, spreading it evenly. Bake for 15 minutes, or until the sauce is bubbly around the edges. Remove the dish from the oven. Carefully sprinkle about half of the crispy shallots evenly over the top (reserving the rest). Return to the oven for 3-5 minutes, just until the topping is warm but not burned. Garnish with the remaining crispy shallots just before serving to maximize the crunch.