Ingredients:

  • 4 tablespoons (57g) unsalted butter
  • 1/4 cup (30g) all-purpose flour
  • 4 cups (946ml) whole milk, warmed
  • 1/4 teaspoon freshly grated nutmeg
  • Salt and freshly ground black pepper to taste
  • 2 tablespoons (30ml) olive oil
  • 1 pound (454g) cremini mushrooms, sliced
  • 2 cloves garlic, minced
  • 10 ounces (283g) fresh spinach, roughly chopped
  • 1/4 cup (60ml) heavy cream
  • Salt and freshly ground black pepper to taste
  • 1 pound (454g) lasagna noodles, no-boil variety recommended
  • 15 ounces (425g) ricotta cheese, whole milk
  • 1/2 cup (50g) grated Parmesan cheese, plus more for topping
  • 2 cups (226g) shredded mozzarella cheese, divided

Instructions:

  1. Melt butter in a saucepan, whisk in flour, and cook for 1-2 minutes. Gradually whisk in warm milk until smooth. Simmer, stirring constantly, until thickened. Stir in nutmeg, salt, and pepper. Remove from heat.
  2. Heat olive oil in a large skillet. Add mushrooms and cook until softened and browned. Add garlic and cook for 1 minute more. Stir in spinach until wilted. Stir in heavy cream, salt, and pepper. Remove from heat.
  3. In a bowl, mix ricotta cheese and Parmesan cheese.
  4. Spread a thin layer of béchamel sauce in the baking dish. Layer lasagna noodles, ricotta mixture, spinach and mushroom filling, béchamel sauce, and mozzarella cheese. Repeat layers. Top with remaining béchamel, mozzarella, and Parmesan cheese.
  5. Cover with foil and bake at 375°F (190°C) for 30 minutes. Remove foil and bake for an additional 15-20 minutes, or until golden brown and bubbly.
  6. Let stand for 10-15 minutes before slicing and serving.