Ingredients:

  • 3 large shallots, very thinly sliced
  • 1/4 cup all-purpose flour (for shallots)
  • 4 cups neutral frying oil (e.g., vegetable, rapeseed, or canola)
  • 1/2 tsp fine sea salt (for shallots)
  • 2 lbs fresh French or haricot green beans, trimmed
  • 1 tbsp coarse sea salt (for blanching water)
  • 4 tbsp unsalted butter (or reserved shallot frying oil)
  • 8 oz mixed mushrooms (cremini/button), cleaned and thinly sliced
  • 2 cloves garlic, minced
  • 1/4 cup all-purpose flour (for velouté)
  • 1 ½ cups chicken or vegetable stock, low sodium (warm is best)
  • 1 cup heavy cream (double cream), room temperature
  • 1/2 tsp dried thyme
  • 1/4 tsp freshly grated nutmeg
  • Salt and freshly ground black pepper, to taste

Instructions:

  1. Blanch the Beans: Bring a large pot of salted water to a rolling boil. Drop the trimmed green beans into the water. Cook for 3–4 minutes until bright green and tender-crisp. Immediately plunge into an ice bath to stop the cooking and set the color. Drain thoroughly and set aside.
  2. Prepare Shallots: Toss the thinly sliced shallots with 1/4 cup of flour until lightly coated. Heat the frying oil in a deep pan to 160°C (320°F).
  3. Fry Shallots: Fry the shallots in batches, stirring often, until deep golden brown and crispy (approx. 4–6 minutes per batch). Watch carefully, as they burn quickly. Remove shallots with a slotted spoon and immediately spread them onto a wire rack. Sprinkle generously with salt while still hot.
  4. Reserve Oil: Pour the frying oil through a sieve. Reserve 4 tablespoons of this flavorful oil for the sauce, or use unsalted butter as an alternative.
  5. Sauté Mushrooms: Melt the reserved oil or butter in a medium saucepan over medium-high heat. Add the sliced mushrooms and sauté until they have released their liquid and browned nicely (approx. 6–8 minutes). Season lightly with salt, pepper, and thyme. Add minced garlic and cook for 1 minute until fragrant.
  6. Make the Roux: Sprinkle the remaining flour over the mushroom mixture. Cook, stirring constantly, for 1–2 minutes to cook out the raw flour taste.
  7. Whisk in Liquid: Slowly whisk in the warm stock until smooth and the sauce thickens slightly. Bring to a gentle simmer.
  8. Add Cream and Season: Reduce heat to low. Stir in the heavy cream and nutmeg. Simmer gently for 3–5 minutes until the sauce is thick enough to coat the back of a spoon. Taste and adjust seasoning aggressively.
  9. Assembly and Bake: Preheat the oven to 180°C (350°F). Gently fold the blanched green beans into the mushroom velouté in a large bowl, ensuring they are evenly coated. Pour the mixture into the prepared 9x13 inch baking dish.
  10. Bake Initial: Bake, uncovered, for 20 minutes, until the sauce is bubbly and heated through.
  11. Finish and Serve: Remove the casserole from the oven. Sprinkle two-thirds of the crispy shallots evenly over the top. Return the casserole to the oven for 5–10 minutes, just until the shallots are warmed. Rest for 5 minutes and garnish with the remaining crispy shallots just before serving to maximize crunch.