Savory Cheesy Spinach Zucchini Lasagna

Getting a nutritious dinner on the table that everyone will actually eat can feel like an impossible task some nights. Between after-school activities, work deadlines, and picky eaters, the dinner rush often leaves us reaching for takeout menus or falling back on the same old pasta dishes we’ve made a hundred times before.

That’s why this cheesy spinach zucchini lasagna has become such a lifesaver in our house – it’s a clever way to sneak in extra vegetables, satisfies even the biggest comfort food cravings, and can be prepped ahead of time for those especially busy evenings.

What Kind of Zucchini Should I Use?

For lasagna, medium-sized zucchini (about 7-8 inches long) are your best bet since they’re easier to slice into even planks and aren’t as seedy as larger ones. Look for zucchini that feels firm and heavy for its size, with smooth, blemish-free dark green skin. If you can only find larger zucchini, just be sure to trim away the seedy center before slicing, as those seeds can make your lasagna watery. When cutting your zucchini planks, try to keep them around 1/8-inch thick so they’ll cook evenly and help hold your lasagna layers together nicely.

Options for Substitutions

This veggie-packed lasagna is pretty flexible with substitutions. Here’s what you can swap:

• Cremini mushrooms: You can use white button mushrooms, portobello (chopped), or shiitake mushrooms. If you’re not a mushroom fan, try finely diced eggplant or extra zucchini instead.
• Baby spinach: Regular spinach works fine – just remove the stems. You can also use frozen spinach (thawed and well-drained) or swap in kale or Swiss chard.
• Ricotta cheese: Cottage cheese (drained and blended) makes a great substitute. For a dairy-free version, try mashed firm tofu with a bit of lemon juice and nutritional yeast.
• Mozzarella and Parmesan: Feel free to use full-fat versions, or try other melting cheeses like provolone or fontina. For Parmesan, pecorino romano or asiago work well too.
• Oven-ready lasagna noodles: Regular lasagna noodles work fine – just cook them first. For a low-carb option, use more zucchini planks instead of pasta.
• Zucchini: Yellow summer squash can be used exactly the same way. Just make sure to slice it thin like the zucchini.

Watch Out for These Mistakes While Cooking

The biggest challenge when making zucchini lasagna is dealing with excess moisture – to prevent a watery dish, make sure to salt your zucchini planks and let them sit for 15-20 minutes, then pat them thoroughly dry with paper towels before assembling.

When cooking the mushrooms, avoid overcrowding the pan and resist the urge to stir them too frequently – give them space and time to release their moisture and brown properly, which usually takes about 8-10 minutes.

A common error is layering the ingredients too thickly – keep your layers relatively thin and even, especially with the ricotta mixture, to ensure everything cooks uniformly and each bite has a perfect balance of flavors.

For the best texture, let the lasagna rest for at least 15 minutes after baking, which allows the layers to set and makes it much easier to cut clean, presentable slices.

What to Serve With Zucchini Lasagna?

This lighter take on lasagna pairs perfectly with a simple side of garlic bread or crusty Italian bread to soak up any extra sauce. Since the lasagna is already packed with veggies, I like to keep the sides pretty straightforward – a basic green salad with a light vinaigrette dressing does the trick nicely. If you want to round out the meal even more, try serving it with some roasted cherry tomatoes or sautéed broccolini on the side. For a true Italian dinner experience, finish the meal with a small scoop of lemon sorbet or a few biscotti!

Storage Instructions

Keep Fresh: This cheesy spinach zucchini lasagna is perfect for leftovers! Cover it tightly with foil or transfer portions to airtight containers and keep in the fridge for up to 4 days. The flavors actually get better as they meld together over time.

Freeze: You can freeze this lasagna either baked or unbaked. If freezing the whole dish, wrap it well in foil and freeze for up to 3 months. For individual portions, cut into squares and store in freezer-safe containers. Just remember to thaw it in the fridge overnight before you plan to eat it.

Reheat: To warm up your lasagna, cover with foil and pop it in the oven at 350°F for about 20-25 minutes until heated through. For single portions, the microwave works great too – heat on medium power for 2-3 minutes, adding a splash of water if it seems dry. The cheese will get all melty and good again!

Preparation Time	20-30 minutes
Cooking Time	45-60 minutes
Total Time	65-90 minutes
Level of Difficulty	Medium

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 1800-2000
• Protein: 85-95 g
• Fat: 105-115 g
• Carbohydrates: 160-180 g

Ingredients

For the vegetables:

• 1/4 tsp black pepper
• 1 medium zucchini (cut into 1/8-inch lengthwise slices, I use a mandoline for this)
• 1 (11 oz) bag baby spinach (for optimal wilting)
• 3 tbsp extra-virgin olive oil
• 1 lb cremini mushrooms (thinly sliced will cook faster)
• 1 garlic clove (finely chopped for even flavor distribution)
• 1/2 tsp salt

For the cheese filling:

• 1 (15 oz) tub part-skim ricotta cheese
• 1 cup shredded part-skim mozzarella (freshly shredded melts best)
• 1/2 cup grated parmesan
• 1 large egg (beaten lightly to combine easily)

For assembly:

• 1/2 cup shredded part-skim mozzarella (plus more for topping if desired)
• 6 sheets oven-ready lasagna noodles
• 1 (25 oz) jar marinara sauce (I like Rao’s Homemade for great flavor)
• 1/2 cup grated parmesan

For garnish:

• Chopped fresh basil and/or parsley

Step 1: Preheat Oven and Prepare Baking Dish

Preheat your oven to 375°F.

Generously coat a 9-by-13-inch baking dish with cooking spray to prevent sticking.

Step 2: Cook the Mushrooms

• 2 tablespoons extra-virgin olive oil
• 1 lb cremini mushrooms, thinly sliced
• 1 garlic clove, finely chopped
• 1/2 tsp salt
• 1/4 tsp ground black pepper

Heat 2 tablespoons of the extra-virgin olive oil in a large skillet over medium-high heat.

Add the sliced cremini mushrooms, chopped garlic, salt, and black pepper.

Cook, stirring occasionally, until the mushrooms become tender and start to brown, which should take about 6 to 8 minutes.

Transfer the cooked mushrooms to a small bowl and set aside.

I like to let the mushrooms caramelize a bit for extra flavor before removing them from the pan.

Step 3: Wilt and Drain the Spinach

• 1 tablespoon extra-virgin olive oil
• 1 (11 oz) bag baby spinach

In the same skillet, heat the remaining 1 tablespoon of olive oil over medium heat.

Add half the baby spinach and cook, stirring frequently, until wilted, about 3 minutes.

Gradually add the remaining spinach by the handful, cooking until all is wilted, another 2 minutes.

Push the spinach to the side of the pan and press out as much water as you can.

Continue cooking until any remaining water has evaporated, 2 to 3 minutes more.

Remove from heat.

Step 4: Slice the Zucchini

• 1 medium zucchini, cut into 1/8-inch lengthwise slices

Slice the zucchini lengthwise into 1/8-inch thick strips.

Set aside for layering in the lasagna.

For more even slices, I use a mandoline slicer, but a sharp knife works too.