Ingredients:

  • 1.5 lbs (680g) fresh green beans, trimmed
  • 1 tablespoon (15ml) olive oil
  • 1/2 teaspoon kosher salt
  • 1/4 teaspoon black pepper
  • 2 large shallots, thinly sliced into rings
  • 1/2 cup (60g) all-purpose flour
  • 1/4 teaspoon kosher salt
  • Vegetable oil for baking
  • 4 tablespoons (57g) unsalted butter
  • 8 oz (227g) cremini mushrooms, sliced
  • 1 medium yellow onion, diced
  • 2 cloves garlic, minced
  • 1/4 cup (30g) all-purpose flour
  • 2 cups (473ml) vegetable broth (low sodium preferred)
  • 1 cup (236ml) whole milk
  • 1/4 cup (60ml) heavy cream
  • 2 tablespoons dry sherry (optional)
  • 1/2 teaspoon kosher salt (more to taste)
  • 1/4 teaspoon black pepper (more to taste)
  • 1/4 teaspoon grated nutmeg

Instructions:

  1. Blanch green beans in boiling salted water until bright green and slightly tender-crisp (about 3-4 minutes). Immediately plunge into an ice bath to stop cooking. Drain well and set aside.
  2. Toss shallot rings with flour and salt. Arrange in a single layer on a baking sheet that’s been lightly oiled or sprayed with cooking spray. Bake at 350°F (175°C) until golden brown and crispy (about 20-25 minutes), flipping halfway through. Set aside to cool on a wire rack.
  3. Melt butter in a large skillet or Dutch oven over medium heat. Add onion and cook until softened. Add garlic and cook until fragrant.
  4. Add sliced mushrooms to the skillet. Cook until softened and browned, releasing their moisture.
  5. Sprinkle flour over the mushroom mixture and cook for 1 minute, stirring constantly to create a roux.
  6. Gradually whisk in vegetable broth and milk until smooth. Bring to a simmer, stirring constantly, until the sauce thickens.
  7. Stir in heavy cream, sherry (if using), salt, pepper, and nutmeg. Taste and adjust seasoning as needed.
  8. Gently fold the blanched green beans into the mushroom sauce.
  9. Pour the green bean mixture into a greased 9x13 inch baking dish.
  10. Generously sprinkle the crispy shallots over the top of the casserole.
  11. Bake in a preheated oven at 350°F (175°C) for 20 minutes, or until bubbly and heated through.
  12. Let stand for a few minutes before serving.