Ingredients:

  • 2 lbs (900g) fresh green beans, trimmed
  • 1 tbsp (15ml) olive oil
  • 1/2 tsp (2.5ml) salt
  • 1/4 tsp (1.25ml) black pepper
  • 2 tbsp (30ml) unsalted butter
  • 1 medium yellow onion, finely chopped (about 1 cup / 150g)
  • 1 lb (450g) cremini mushrooms, sliced
  • 2 cloves garlic, minced
  • 1/4 cup (60ml) all-purpose flour
  • 2 cups (475ml) vegetable broth (low-sodium)
  • 1 cup (240ml) milk (whole or 2%)
  • 1/4 cup (60ml) dry sherry (optional, but highly recommended)
  • 1 tsp (5ml) Dijon mustard
  • 1/4 tsp (1.25ml) nutmeg
  • Salt and pepper to taste
  • 2 large shallots, thinly sliced
  • 1/4 cup (60ml) all-purpose flour
  • 1/4 tsp (1.25ml) salt
  • 1/4 cup (60ml) vegetable oil (or other high-heat oil)
  • 1/4 cup (60ml) chopped fresh parsley (for garnish, optional)

Instructions:

  1. Blanch green beans in boiling salted water until bright green and crisp-tender. Shock in ice water, drain well, and toss with olive oil, salt, and pepper.
  2. Toss shallot slices with flour and salt. Fry in hot oil until golden brown and crispy. Drain on paper towels and set aside.
  3. Melt butter in a large skillet. Sauté onion and mushrooms until softened and browned. Add garlic and cook until fragrant.
  4. Sprinkle flour over the mushroom mixture and cook for 1 minute. Gradually whisk in vegetable broth and milk until smooth. Bring to a simmer and cook until thickened.
  5. Stir in sherry (if using), Dijon mustard, and nutmeg. Season with salt and pepper to taste.
  6. Combine green beans and mushroom sauce in the baking dish.
  7. Bake in a preheated oven at 350°F (175°C) until bubbly and heated through.
  8. Sprinkle crispy shallots over the casserole and bake for an additional 5-10 minutes, until shallots are golden brown.
  9. Garnish with fresh parsley (if desired) and serve hot.