Ingredients:

  • 4 large Shallots (or small yellow onions), thinly sliced
  • 1/2 cup All-Purpose Flour (for dredging)
  • 1 tsp Salt (for shallots)
  • 4 cups Vegetable Oil (e.g., Canola, Peanut), for deep frying
  • 2 lbs Fresh Green Beans (Haricots Verts preferred), trimmed
  • Salt (to taste, for blanching water)
  • 4 Tbsp Unsalted Butter
  • 8 oz Cremini Mushrooms, thinly sliced
  • 2 cloves Garlic, minced
  • 1/4 cup All-Purpose Flour (for the roux)
  • 1/2 cup Chicken or Vegetable Stock (low sodium)
  • 2 cups Whole Milk, warmed
  • 1/2 cup Heavy Cream
  • 1/2 cup (packed) Gruyère or Sharp White Cheddar Cheese, freshly grated
  • 1/4 tsp Nutmeg, freshly grated
  • Salt and Black Pepper (to taste)

Instructions:

  1. Blanch the Beans: Bring a large pot of heavily salted water to a rolling boil. Add trimmed green beans and cook for 4-5 minutes until crisp-tender (al dente). Immediately plunge beans into an ice bath to stop cooking and retain a vibrant green colour. Drain thoroughly and set aside.
  2. Fry the Shallots: In a medium bowl, toss thinly sliced shallots with the dredging flour and salt until lightly coated. Shake off excess flour. Heat oil in a deep saucepan or Dutch oven to 325°F (160°C). Working in batches, fry the shallots until golden brown and crisp (about 3–4 minutes per batch). Remove with a slotted spoon and drain immediately on a paper towel-lined wire rack. Season lightly with salt while warm.
  3. Sauté Aromatics: Melt the butter in a large saucepan over medium heat. Add the sliced mushrooms and sauté until they release their moisture and brown slightly (about 5-7 minutes). Add the minced garlic and cook for 1 minute until fragrant.
  4. Make the Roux: Sprinkle the 1/4 cup of flour over the mushroom mixture. Stir continuously for 1 minute to cook out the raw flour taste.
  5. Build the Sauce: Slowly whisk in the warmed milk and chicken stock, ensuring no lumps form. Bring to a gentle simmer, whisking frequently until the sauce thickens (about 5 minutes).
  6. Finish the Sauce: Reduce heat to low. Stir in the heavy cream, grated cheese, nutmeg, salt, and pepper. Stir until the cheese is fully melted and the sauce is smooth and luxurious. Taste and adjust seasoning.
  7. Combine and Transfer: Preheat oven to 375°F (190°C). Gently fold the blanched green beans into the creamy mushroom béchamel sauce until evenly coated. Pour the mixture into a prepared 9x13 inch casserole dish.
  8. Bake: Bake for 25-30 minutes, or until the sauce is bubbly and the casserole is heated through and lightly golden on top.
  9. Rest and Serve: Remove from the oven. Let the casserole rest for 5-10 minutes. Scatter the homemade crispy shallots generously over the top just before serving to ensure maximum crunch.