Ingredients:

  • 2 lbs Fresh Green Beans (Trimmed and cut)
  • 1 Tbsp Coarse Salt (For blanching)
  • Ice Water (As needed)
  • 4 Tbsp Unsalted Butter (Divided)
  • 8 oz Crimini Mushrooms (Sliced or quartered)
  • 2 large Shallots (Finely diced)
  • 1/4 cup All-Purpose Flour
  • 1 cup Chicken Stock (or Vegetable Stock)
  • 1 cup Heavy Cream (Double Cream)
  • 1 tsp Fresh Thyme Leaves (Finely chopped)
  • 1/2 tsp Garlic Powder
  • Pinch Freshly Grated Nutmeg
  • Kosher Salt & Black Pepper (To taste)
  • 3 cups Store-Bought Crispy Fried Onions (Divided)
  • 1/2 cup Panko Breadcrumbs
  • 1 Tbsp Unsalted Butter (Melted, for topping)

Instructions:

  1. Blanch the Beans: Bring a large pot of heavily salted water to a rolling boil. Drop in the trimmed green beans and cook for 3 to 4 minutes until they are bright green and slightly tender (al dente).
  2. Shock: Immediately transfer the beans to a large bowl of ice water (this halts the cooking process and locks in the colour). Drain thoroughly and set aside.
  3. Sauté Aromatics: In a large saucepan, melt 2 Tbsp of butter over medium heat. Add the mushrooms and cook until browned (about 5-7 minutes). Add the diced shallots and cook until softened (2-3 minutes). Remove the mushroom mixture and set aside.
  4. Make the Roux: Melt the remaining 2 Tbsp of butter in the same saucepan. Whisk in the flour and cook for 1 to 2 minutes, ensuring a smooth, light-coloured paste (a pale blonde roux).
  5. Build the Sauce: Slowly whisk in the chicken stock, scraping up any bits from the bottom. Once smooth, slowly whisk in the heavy cream.
  6. Simmer and Season: Bring the sauce to a gentle simmer, stirring constantly, until thickened sufficiently to coat the back of a spoon (about 3-4 minutes). Reduce heat to low. Stir in the garlic powder, thyme, nutmeg, salt, and pepper.
  7. Combine Filling: Fold the sautéed mushroom and shallot mixture back into the cream sauce. Taste and adjust seasoning.
  8. Preheat and Prepare Topping: Preheat the oven to 375°F (190°C). Grease the 9x13 inch baking dish. In a small bowl, combine the Panko breadcrumbs with 1 Tbsp melted butter.
  9. Mix Casserole: Gently combine the drained, blanched green beans and the cream sauce in a large bowl. Pour the mixture evenly into the prepared baking dish.
  10. First Bake: Sprinkle 2 cups of the crispy fried onions and all of the Panko mixture over the top.
  11. Bake: Bake for 20 minutes, or until the sauce is bubbly and the topping is golden brown.
  12. Final Topping: Remove the casserole from the oven and scatter the remaining 1 cup of crispy fried onions over the top. Return to the oven for a final 5 minutes until the topping is hot and fragrant.
  13. Serve: Let rest for 5-10 minutes before serving.