This sheet pan spinach lasagna takes all the comforting flavors of a classic baked lasagna and streamlines them into a single, manageable pan. Instead of layering in a deep dish, the noodles are broken and scattered, the sauce is spread, and the cheese is sprinkled, creating a deliciously chaotic yet perfectly satisfying dish. It’s a fantastic weeknight dinner that delivers all the cheesy, saucy goodness with far less fuss and a quicker bake time.
Ingredients
- 12 ounces (about 340g) lasagna noodles, broken into 2-inch pieces
- 2 tablespoons olive oil
- 1 medium yellow onion, finely chopped
- 4 cloves garlic, minced
- 10 ounces (about 280g) frozen chopped spinach, thawed and squeezed very dry
- 1 (24-ounce) jar of your favorite marinara or pasta sauce (about 3 cups)
- 1 cup water
- 1 teaspoon dried oregano
- 1/2 teaspoon red pepper flakes (optional)
- Salt and freshly ground black pepper, to taste
- 15 ounces (about 425g) ricotta cheese
- 1 large egg
- 1/2 cup grated Parmesan cheese, plus more for serving
- 3 cups shredded mozzarella cheese (about 12 ounces)
- Fresh basil leaves, for garnish (optional)
Instructions
- Preheat your oven to 400°F (200°C). Lightly grease a large, rimmed sheet pan (about 13×18 inches) with olive oil or non-stick spray.
- In a large skillet over medium heat, warm the olive oil. Add the chopped onion and cook until softened, about 5 minutes. Add the minced garlic and cook for another minute until fragrant.
- Add the squeezed-dry spinach to the skillet, breaking it up with a spoon. Cook for 2-3 minutes to remove any excess moisture. Season with a pinch of salt and pepper.
- Pour the marinara sauce, water, oregano, and red pepper flakes (if using) into the skillet. Stir to combine and bring to a gentle simmer. Cook for about 5 minutes, allowing the sauce to thicken slightly.
- While the sauce simmers, prepare the ricotta mixture. In a medium bowl, combine the ricotta, egg, and grated Parmesan. Mix well and set aside.
- Spread the broken lasagna noodles evenly across the prepared sheet pan.
- Pour the hot sauce mixture over the noodles. Use a spatula to toss everything together, ensuring the noodles are well coated and mostly submerged in the sauce.
- Dollop the ricotta mixture over the top of the saucy noodles. Use a spoon to gently spread it around a bit, but don’t worry about covering every bit—large clumps are fine.
- Sprinkle the shredded mozzarella evenly over the entire pan.
- Cover the sheet pan tightly with aluminum foil. Bake for 25 minutes.
- Remove the foil and continue baking for another 15-20 minutes, until the cheese is bubbly and golden brown and the noodles are tender.
- Let the lasagna rest for at least 10 minutes before slicing and serving. This allows the sauce to settle and makes it easier to cut into neat squares. Garnish with fresh basil, if desired.
Tips
- Don’t skip squeezing the spinach: Thawed frozen spinach holds a lot of water. Squeeze it thoroughly, a handful at a time, to remove as much liquid as possible. This prevents the lasagna from becoming watery.
- Use no-boil noodles if you prefer: You can substitute no-boil (oven-ready) lasagna noodles. Since they are thinner, you may not need the full cup of water in the sauce. Start with 3/4 cup of water and check the consistency after baking—the noodles will absorb liquid as they cook.
- Make it ahead: You can assemble the entire lasagna on the sheet pan (without baking) up to a day in advance. Cover and refrigerate. When ready to bake, add about 10-15 minutes to the covered baking time since you’re starting from cold.
- Watch the noodle coverage: Ensure the noodles are in a single, even layer as much as possible. Overlapping noodles might not cook through properly. If you have a lot of overlap, add a little extra water to the sauce.
Serving Suggestions
This sheet pan lasagna is a complete meal on its own, but it pairs beautifully with a simple green salad dressed with lemon vinaigrette and a side of crusty garlic bread to soak up any extra sauce. A sprinkle of fresh basil or a pinch of red pepper flakes right before serving adds a nice pop of color and flavor. It’s also great for feeding a crowd—just cut it into squares and let everyone serve themselves.
Variations
- Meat Lover’s: Brown 1 pound of ground beef or Italian sausage with the onion and garlic. Drain any excess fat, then proceed with the recipe.
- Mushroom & Kale: Sauté 8 ounces of sliced mushrooms with the onion and replace the spinach with chopped kale (no need to thaw, just massage it with a little olive oil).
- White Lasagna: Skip the marinara and make a quick white sauce by whisking 2 cups of milk with 2 tablespoons of flour and 2 tablespoons of butter until thickened. Use that instead of the red sauce, and add a pinch of nutmeg to the ricotta mixture.
- Vegan/Vegetarian: Use a dairy-free ricotta and mozzarella alternative, and replace the egg with a flax egg (1 tablespoon ground flaxseed mixed with 3 tablespoons water). The rest of the recipe remains the same.
Storage and Reheating
Store any leftover lasagna in an airtight container in the refrigerator for up to 4 days. To reheat, place a portion on a microwave-safe plate and heat in 30-second intervals until warmed through. For a crispier texture, reheat in a 350°F (175°C) oven for 10-15 minutes, or until hot and bubbly. You can also freeze the baked lasagna for up to 2 months. Wrap the entire sheet pan tightly in plastic wrap and then foil, or transfer individual portions to freezer-safe containers. Thaw overnight in the refrigerator before reheating.
Frequently Asked Questions
Can I use regular lasagna noodles without boiling them first? Yes, that’s the beauty of this recipe. The extra water in the sauce and the covered baking time allow the noodles to cook directly in the sauce. Just make sure they are broken into pieces and well-coated.
My lasagna came out a bit watery. What went wrong? The most common culprit is not squeezing the spinach dry enough. Another possibility is using a very thin pasta sauce. If your sauce is thin, you can reduce the water in the recipe to 3/4 cup. Also, letting the lasagna rest after baking helps the sauce thicken as it cools.
Can I make this in a regular 9×13 baking dish? Absolutely, but you’ll need to adjust the baking time. A 9×13 dish is deeper than a sheet pan, so you’ll likely need to increase the covered baking time to about 30 minutes and the uncovered time to 20-25 minutes, or until the noodles are tender.
Can I use fresh spinach instead of frozen? Yes. Use about 10 ounces of fresh spinach, roughly chopped. Sauté it in the skillet with the onion until wilted, about 3-4 minutes, and then proceed. You won’t need to squeeze it, but be aware it will release some liquid as it cooks.
How do I know when the lasagna is done? The noodles should be tender when pierced with a fork, and the cheese on top should be melted and golden brown. The sauce should be bubbling around the edges.
What if I don’t have ricotta cheese? You can substitute cottage cheese (drained) or even a mixture of cream cheese and a little milk. The texture will be slightly different, but it will still be delicious.