- 14 plum tomatoes (about 3 pounds total), halved lengthwise
- 1/4 cup extra-virgin olive oil, plus more for baking dish
- 1 teaspoon dried oregano
- 3 garlic cloves, thinly sliced
- Coarse salt and ground pepper
- 1 medium butternut squash, peeled, seeded, and sliced inch thick
- 3 bunches (about 2 1/2 pounds total) spinach, trimmed and washed
- 1 container (15 ounces) whole-milk ricotta
- 1/2 cup grated Parmesan
- 1 egg
- 1/4 teaspoon ground or freshly grated nutmeg
- 9 to 12 no-boil lasagna noodles (from a 9-ounce package)
- 1 pound fresh mozzarella, cut into pieces
- Preheat oven to 400 degrees, with racks in upper and lower thirds. On a rimmed baking sheet, toss tomatoes with 2 tablespoons oil, oregano, and two-thirds the garlic; season with salt and pepper. Brush another rimmed baking sheet with 1 tablespoon oil. Arrange squash in one layer; season with salt and pepper. Roast squash until tender, about 20 minutes, and tomatoes until slightly shriveled, about 40 minutes, rotating sheets halfway through. In a blender, puree 20 tomato halves. Season with salt and pepper; set aside.
- In a large skillet, heat 1 tablespoon oil over medium-high. Add remaining garlic and cook, stirring, 30 seconds. Gradually add 2 pounds spinach and toss until wilted, about 4 minutes. Transfer spinach to a strainer and press to release liquid. When cool, chop spinach and season with salt and pepper. In a large bowl, mix ricotta, cup Parmesan, egg, and nutmeg until smooth; season with salt and pepper.
- Lightly oil a 9-inch square baking dish. Spread one-quarter the tomato sauce in dish, top with 3 to 4 noodles, breaking to fit as needed. Top with half the ricotta mixture, half the squash, one-quarter the tomato sauce, and 3 to 4 noodles. Top with remaining ricotta mixture, cooked spinach, one-quarter the sauce, and 3 to 4 noodles. Top with remaining sauce, 1/2 pound mozzarella, and cup Parmesan.
- Set rack in middle of oven. Bake lasagna on a rimmed baking sheet until golden brown, 30 to 35 minutes. Let lasagna cool 15 minutes before serving.
What to Save: For tomorrow's lunch, reserve half the roasted squash, 8 roasted tomato halves, 1/2 pound fresh spinach, and 1/2 pound mozzarella.