Ingredients:

  • 450 g Fresh Green Beans (Haricot Verts preferred), trimmed and halved
  • 1 tsp Salt (for blanching water)
  • 4 medium Shallots (approx. 200 g), thinly sliced into rings (or substitute 1 medium yellow onion)
  • 1/4 cup All-Purpose Flour (for coating shallots)
  • 1 tbsp Cornstarch
  • 1/2 tsp Kosher Salt
  • 2 cups Neutral Oil (e.g., Vegetable, Canola), for shallow frying
  • 4 tbsp Unsalted Butter, divided
  • 340 g Cremini Mushrooms, sliced thinly
  • 2 cloves Garlic, minced
  • 1/2 tsp Fresh Thyme Leaves (or 1/4 tsp dried)
  • 3 tbsp All-Purpose Flour (for the roux)
  • 1 1/2 cups Chicken or Vegetable Stock (low sodium), warm
  • 1/2 cup Whole Milk or Half-and-Half
  • 1/4 cup Heavy Cream
  • 1 tsp Worcestershire Sauce
  • Salt and freshly ground Black Pepper, to taste

Instructions:

  1. Blanch the Green Beans: Bring a large pot of salted water to a rolling boil. Add trimmed beans and cook for 3-4 minutes until bright green and tender-crisp (al dente). Immediately plunge into an ice bath to stop cooking and preserve colour. Drain thoroughly and set aside.
  2. Prepare the Shallots: Toss the thinly sliced shallots with the flour, cornstarch, and salt mixture until evenly coated.
  3. Fry the Shallots: Heat the neutral oil in the heavy saucepan to 350°F (175°C). Fry the shallots in small batches, stirring often, for 2–4 minutes until deeply golden brown and crisp.
  4. Drain: Remove shallots with a slotted spoon and immediately spread them onto a tray lined with paper towels. Season lightly with extra salt while hot. Set aside.
  5. Sauté the Mushrooms: In the same saucepan (wiped clean), melt 2 tablespoons of butter over medium-high heat. Add the sliced mushrooms and sauté until they have released their liquid and are nicely browned (about 5–7 minutes). Season with salt and pepper.
  6. Add Aromatics: Stir in the garlic and fresh thyme; cook for 1 minute until fragrant. Remove the mushroom mixture from the pan and set aside.
  7. Make the Roux: Melt the remaining 2 tablespoons of butter in the empty pan. Whisk in the 3 tablespoons of flour. Cook, stirring constantly, for 1–2 minutes until the mixture (the roux) is smooth and smells slightly nutty.
  8. Whisk in Liquids: Slowly whisk in the warm stock until smooth, ensuring no lumps remain. Then, slowly whisk in the milk/half-and-half.
  9. Simmer and Thicken: Bring the mixture to a gentle simmer, whisking frequently. Reduce heat and cook for 3–5 minutes until the sauce has thickened sufficiently to coat the back of a spoon.
  10. Finish the Sauce: Remove from heat. Stir in the heavy cream and Worcestershire sauce. Taste and adjust seasoning (salt and pepper). Stir the reserved mushroom mixture back into the sauce.
  11. Preheat Oven: Preheat your oven to 375°F (190°C). Grease the 9x13 inch baking dish.
  12. Combine: Gently fold the blanched green beans into the creamy mushroom sauce until they are fully coated. Pour the mixture into the prepared baking dish.
  13. Bake (Initial): Bake for 15–20 minutes, or until the sauce is bubbly around the edges.
  14. Top and Finish: Remove the casserole from the oven. Evenly sprinkle three-quarters (3/4) of the crispy shallots over the top. Return to the oven for a final 5 minutes to heat the topping slightly.
  15. Rest and Serve: Allow the casserole to rest for 5–10 minutes before serving. Garnish with the remaining crispy shallots just before bringing it to the table.