Classic Vegetable Lasagna

Classic vegetable lasagna is a layered casserole of tender pasta, roasted vegetables, and two kinds of cheese bound with a tomato sauce. It is comforting, filling, and stays together when you slice it because the vegetables release their moisture slowly as the lasagna bakes.

Ingredients for Classic Vegetable Lasagna

Lasagna noodles form the structure and soften during baking. Zucchini and eggplant are roasted first to remove water so the filling does not get soupy. Spinach adds color and flavor without adding liquid if you squeeze it dry. Ricotta cheese is mild and spreads easily between layers. Mozzarella cheese melts and browns on top. Parmesan cheese adds a sharp bite. Egg binds the cheese mixture. Tomato sauce provides acidity and moisture. Garlic, salt, black pepper, and dried oregano season the whole dish.

Why This Classic Vegetable Lasagna Works

The zucchini and eggplant are roasted before assembly, which cooks off excess water and concentrates their flavor. If you layered them raw, they would release moisture as the lasagna bakes and turn the dish watery and heavy. Roasting takes 20 minutes and saves the texture of the whole dish.

The spinach is thawed and squeezed dry for the same reason. Fresh spinach is mostly water, and wringing it out in a kitchen towel removes the liquid before it reaches the casserole. The egg in the ricotta mixture acts as a binder, helping the layers stay together when you cut and serve.

The lasagna is covered for the first half of baking so the sauce simmers gently and the pasta absorbs it without drying out. Uncovering it for the last 15 minutes allows the cheese on top to brown and the edges to bubble, which is your sign that the center has heated through.

Mistakes To Avoid

Skipping the roasting step is the most common mistake. Raw zucchini and eggplant release water as they bake, making the lasagna soupy and causing the noodles to absorb so much liquid that they fall apart when you cut a slice. The dish tastes heavy and the layers slide around on the plate.

Overcooking the lasagna noodles before assembly is a close second. Soft noodles break apart when you layer them and turn to mush during baking. Cook them until they bend easily but still have a slight firmness at the center, then drain and lay them flat on a clean kitchen towel so they do not stick together.

Forgetting to squeeze the spinach dry makes the filling watery and the cheese layer thin. Spinach that still holds moisture will seep into the sauce and dilute the flavors. Press it hard in a towel until almost nothing drips out, then chop it and fold it into the ricotta.

Leaving the lasagna uncovered for the whole bake causes the top to brown too fast and the noodles underneath to dry out before they soften. Cover the dish with foil for the first 50 minutes so the sauce steams the pasta gently, then uncover it so the cheese can brown and the edges can bubble.

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Ingredients

• 1 pound zucchini, cut into 1/4-inch-thick rounds
• 1 pound eggplant, cut into 1/4-inch-thick rounds
• 3 tablespoons olive oil, divided
• Salt and black pepper to taste
• 10 ounces frozen spinach, thawed
• 15 ounces ricotta cheese
• 2 cups shredded mozzarella cheese, divided
• 1/2 cup grated Parmesan cheese
• 1 large egg
• 3 cloves garlic, minced
• 1 teaspoon dried oregano
• 24 ounces tomato sauce
• 9 lasagna noodles

Step-by-step Instructions

1. Heat the oven to 425°F (220°C). Toss zucchini and eggplant with 2 tablespoons olive oil, salt, and pepper on two baking sheets in a single layer. Roast for 20 minutes until the edges are golden and the vegetables are tender.
2. Meanwhile, bring a large pot of salted water to a boil. Add lasagna noodles and cook for one minute less than the package directs, until they bend easily but still feel slightly firm. Drain and lay flat on a clean kitchen towel.
3. Squeeze the thawed spinach hard in a clean kitchen towel until almost no liquid drips out. Chop it fine.
4. In a medium bowl, mix ricotta, 1 cup mozzarella, Parmesan, egg, spinach, garlic, oregano, salt, and pepper until combined. Stir the tomato sauce in a separate bowl and add salt and pepper to taste.
5. Reduce the oven to 375°F (190°C). Spread a thin layer of tomato sauce on the bottom of a 9×13 baking pan. Lay three noodles across the pan side by side.
6. Spread one third of the ricotta mixture over the noodles. Layer half the roasted vegetables over the ricotta. Spread another third of the ricotta mixture over the vegetables. Lay three noodles on top.
7. Spread the remaining roasted vegetables over the noodles. Spread the last third of ricotta on top. Lay the final three noodles on top. Pour the remaining tomato sauce over the noodles and sprinkle the remaining 1 cup mozzarella on top.
8. Cover the pan tightly with foil. Bake for 50 minutes until the sauce bubbles at the edges and the center reaches 165°F (74°C) on an instant-read thermometer.
9. Remove the foil and bake for 15 minutes more until the cheese on top is golden and the edges are bubbling. Let the lasagna rest for 10 minutes before serving so the layers set and stay together when you cut.