Ingredients:

  • 1 medium butternut squash (approx. 2.5 lbs / 1.1 kg), halved, seeded
  • 1 tbsp olive oil (for roasting)
  • Salt and black pepper, to taste
  • 2 tbsp extra virgin olive oil
  • 1 large yellow onion (200 g), finely diced
  • 4 cloves garlic, minced
  • 16 oz (450 g) chestnut mushrooms, sliced thickly
  • 2 medium zucchini (300 g), diced small
  • 16 oz (450 g) frozen spinach, thawed and very well squeezed
  • 1 tsp dried oregano
  • 4 tbsp (55 g) unsalted butter
  • 4 tbsp (55 g) all-purpose flour
  • 3 cups (710 ml) whole milk
  • 5 cups (350 g) butternut purée (reserved from roasting)
  • ¼ cup (25 g) grated Parmesan cheese, plus extra for topping
  • ½ tsp ground nutmeg
  • White pepper, to taste
  • 15 oz (425 g) whole milk ricotta cheese, drained
  • 8 oz (225 g) low-moisture mozzarella, shredded (divided)
  • ¼ cup fresh basil, chopped roughly
  • 1 large egg
  • 12 sheets no-boil lasagna noodles

Instructions:

  1. Roast the Butternut Squash: Preheat the oven to 400°F (200°C). Rub squash halves with olive oil, season, and roast cut-side down for 35–45 minutes until tender. Scoop out the flesh and purée until completely smooth. Measure out 1.5 cups for the béchamel.
  2. Prepare the Ricotta Mixture: In a medium bowl, combine the ricotta, half of the shredded mozzarella (4 oz / 110g), the egg, chopped basil, a pinch of salt, and pepper. Set aside.
  3. Sauté the Vegetables: Heat 2 tbsp olive oil in a large skillet. Add onions and sauté until translucent (5 mins). Add garlic, mushrooms, and zucchini. Cook until the mushroom liquid evaporates and vegetables are tender and lightly browned (10–12 minutes). Season well with salt, pepper, and oregano.
  4. Incorporate Spinach: Remove the vegetable mixture from the heat. Stir in the thoroughly squeezed, thawed spinach. Ensure the mixture is firm and not watery.
  5. Make the Roux: Melt the unsalted butter in a heavy-bottomed saucepan over medium heat. Whisk in the flour and cook for 1–2 minutes, forming a smooth paste.
  6. Add Milk: Gradually whisk in the cold whole milk until smooth. Bring the mixture to a gentle simmer, stirring constantly, until the sauce thickens and coats the back of a spoon (5–7 minutes).
  7. Finish the Sauce: Remove from heat. Whisk in the 1.5 cups of butternut purée, nutmeg, Parmesan cheese, salt, and white pepper. The butternut béchamel should be thick.
  8. Pre-Heat and Prep: Reduce the oven temperature to 375°F (190°C). Lightly grease the 9x13 inch baking dish.
  9. Layer Assembly: Start with 1 cup of béchamel on the dish bottom. Layer with pasta, half of the vegetable filling, half of the ricotta mixture, and 1.5 cups of béchamel. Repeat the sequence: pasta, remaining vegetables, remaining ricotta, and 1.5 cups more béchamel.
  10. Final Topping: Finish with a final layer of pasta sheets. Pour the remaining béchamel over the top, ensuring full coverage. Sprinkle with the remaining shredded mozzarella (4 oz / 110g) and a dusting of Parmesan.
  11. Bake and Brown: Cover the dish tightly with foil and bake for 30 minutes. Remove the foil and bake for an additional 25–30 minutes, or until golden brown and bubbling.
  12. Rest: Remove the lasagna from the oven and let it rest on a wire rack for a minimum of 15 minutes before slicing. This is crucial for structural integrity.