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This squash lasagna is the ultimate fall comfort food. This squash skillet lasagna is layered with roasted kabocha squash, roasted garlic, caramelized onions, fresh spinach, herbs, aromatics, and melty gruyere cheese. Made in a cast iron skillet, this kobocha squash lasagna recipe is perfect for feeding the whole family and guests.
Kabocha Squash
- What is a kabocha squash? Kabocha squash is a Japanese winter squash, also known as a Japanese pumpkin.
- What does kabocha squash taste like? Kabocha squash is a bit sweeter than butternut squash, but mild in taste. The texture is a cross between a pumpkin and sweet potato.
- How do you eat kabocha squash? Kabocha squash is best enjoyed cut open, seeds removed, and roasted. You can eat the skin, but for this recipe we will not be using the skin.
Prepping kabocha squash
- Kabocha squash are very hard on the outside, please be careful cutting. I use a sharp chefs knife as well as a towel to secure the squash.
- Once you’ve cut the squash in half, scoop the seeds out using a spoon.
- Discard the seeds and proceed to cut the squash into quarter pieces.
- Brush olive oil on all four pieces of the squash and season with kosher salt and black pepper
Roasted garlic
For this squash lasagna recipe, I really wanted to amplify the flavors within the lasagna. One of those being roasted garlic. When garlic is roasted in the oven, it becomes sweeter, caramelized, and more mild in taste. I roast the garlic alongside the kabocha squash in the oven, since they take the same amount of time to roast.
Roasted garlic and kabocha squash
Roast the kabocha squash and garlic head at 400F for 45 minutes. Both the kabocha squash and the garlic cloves should be easily pierced with a knife when they are ready.
Caramelized onions
- Why caramelize onions? When onions are cooked low and slow in a fat, the sugars within transform, leaving you with a complex sweet tasting onion. Caramelizing onions adds a great depth of flavor to dishes.
- Cutting onions: I use a mandoline to cut my onions so they are uniform in size and will cook/caramelize evenly. Please use guard or wear cutting glove when using mandolines.
- Time? Caramelizing onions takes time, but is so worth it in the end. It takes about 45 minutes-1 hour to caramelize onions. Since the kabocha squash takes 45 minutes to roast, it gives you plenty of time to caramelize your onions.
- Wine? I like to add a splash of wine at the end of caramelizing my onions for an extra layer of flavor.
Spinach filling
Once the onions are done caramelizing, add in fresh spinach and sauté until just wilted. This spinach and caramelized onion mixture will be one of the layers in the squash lasagna. Set aside.
Kabocha squash pureé
- To make the kabocha squash purée layer of the lasagna, you can use a blender, immersion blender, or mash by hand. Since the consistency is thick, I recommend hand mashing.
- Scoop out the flesh of the kabocha squash, discard the skin.
- Squeeze the garlic cloves out of the skin of the bulb. You can use a pairing knife to help any bits stuck in the cloves.
- Purée ingredients: kabocha squash, roasted garlic, butter, egg, ricotta cheese, and milk.
- You’re looking for the consistency of mashed potatoes, you can add milk as you go to get desired consistency. Remember you can always add liquid, but you can’t take it away
Cheesy béchamel sauce
- What is béchamel? Béchamel is a French sauce traditionally made from a roux (butter and flour) and milk.
- This sauce starts out traditional with melted butter and flour, whisked until combined, then slowly add the milk while whisking. The sauce will begin to thicken. Once it comes to a gentle boil, I added the herbs and cheese and whisked until melted.
- Cheese: Gruyére is one of my favorite cheeses to melt. It is an Alpine Swiss cheese that is rich, creamy, slightly salty, and nutty. I always grate my own cheese from a block, since pre-shredded cheese usually has anti-caking agents which don’t allow it to melt as smoothly.
- Herbs: In this cheesy béchamel sauce I used fresh sage and thyme.
Assembling squash lasagna
Squash lasagna layer order:
- Cheesy béchamel sauce: Spoon 1/3 of the cheesy bechamel sauce to coat the bottom of the cast iron skillet.
- No-boil lasagna noodles: for this recipe you need to use no-boil lasagna noodles, or if you are using regular lasagna noodles, you must boil them prior to adding them (al dente).
- Kabocha squash roasted garlic purée: dollop some of the squash pureé over the top of the noodles and spread with a spatula to the edges of the cast iron.
- Caramelized onion spinach mix: Add half of the spinach and caramelized onion mix over top of the squash.
- Repeat: Repeat with the half the cheesy bechamel, followed by lasagna noodles, squash purée, spinach mix, and finally the rest of the cheesy bechamel on top.
Baking lasagna
Lasagna baking tip: First cover your lasagna with parchment paper, followed by foil. Putting parchment paper over the lasagna will keep the cheese from sticking to the foil when baking.
Bake the squash skillet lasagna at 400F for 20 minutes covered, then uncovered for 15 minutes. Baking the lasagna covered will allow all the flavors to meld together and soften the no-boil lasagna noodles. Once uncovered, the top of the cheesy béchamel sauce will become golden brown and bubbly.
Once the squash lasagna is complete, allow it to cool for 5 minutes before cutting into it. Since this is a skillet lasagna, it is best served like a pie or you can cut into square pieces.
Making squash lasagna ahead
This squash lasagna can be made ahead of time prior to assembly or after fully assembled.
- If making individual elements ahead of time, cheesy béchamel sauce will have to be reheated prior to using.
- If assembling fully and refrigerating, you may need to bake covered an additional 5-10 minutes since all the elements will be colder.
Storing squash lasagna
To store leftovers: allow the lasagna to fully cool (cast iron will no longer be hot), then you can cut into slices and store in airtight container or transfer the whole to a dish and store.
To reheat leftovers: you can microwave for 2-3 minutes until warm throughout or you can place in the oven at 350F covered for 25-30 minutes or until warmed through.
Looking for other comforting fall recipes?
Looking for other comforting fall recipes?
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Squash Skilet Lasagna
Ingredients
- 1 large Kabocha squash (quartered, deseeded)
- 1 head garlic (top 1/3 cut and removed)
- 3 tablespoons olive oil
- Kosher salt
- Ground black pepper
- 1 stick salted butter (divided)
- 2 yellow onions (peeled, cut in half, sliced thin on mandoline)
- 1/4 cup dry white or red wine
- 6 ounces fresh spinach
- 2 cups freshly grated gruyere cheese
- 1 egg
- 4 ounces ricotta cheese
- 2 1/4 cups whole milk (divided)
- 3 tablespoons all purpose flour
- 2 tablespoons freshly chopped sage
- 2 tablespoons freshly chopped thyme
- 1/4 teaspoon ground nutmeg
- 1 package no-boil lasagna noodles
Equipment
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Instructions
Kabocha squash & garlic
- Preheat oven to 400F
- Using a sharp chef’s knife, carefully cut squash in half. Using a spoon, scoop seeds out of squash and discard. Cut squash halves in half, so that you have 4 pieces of squash.
- Place squash on a baking sheet and brush the insides with olive oil, then liberally salt and pepper each quarter.
- Cut top 1/3 off garlic head. Place on foil and drizzle 1 tbsp of olive oil over exposed cloves. Add a pinch of salt and pepper over the top, then tightly wrap in foil. Place on the baking sheet with the squash.
- Roast for 45 minutes, until the squash and garlic are easily pierced with a fork.
Caramelized onions
- While the squash and garlic roasts, caramelize onions. In a dutch oven over medium-low heat, add in 3 tbsp butter and melt. Once melted, add in the sliced onions.
- Cook the onions down, mixing every so often, until they are caramelized, about 45 minutes. They should be dark amber and jammy once finished.
- Once onions are caramelized, add in 1/4 cup of wine and allow the liquid to reduce for 3 minutes. Add in the spinach and allow to just wilt, about 2-3 minutes. Remove from heat and set aside.
Squash purée
- For this next part you can use a blender or hand mash, since the consistency is thick I recommend hand mash. Once the squash is done roasting, scoop the flesh out and discard the skin of the squash. Add squash to bowl or blender. Squeeze garlic cloves and using a pairing knife to get any cloves in the skin.
- Add egg, ricotta cheese, 1/4 cup milk and 2 tbsp butter to the squash and garlic. Mix until ingredients are incorporated. You’re looking for the consistency of mashed potatoes. You can add additional milk to thin out, but remember you can always add liquid, but you can’t take away. Set aside once combined.
Cheesy béchamel sauce
- In the dutch oven over medium heat, add 3 tbsp butter and allow to melt. Once melted, add in the 3 tbso flour and whisk to combine. Slowly begin pouring in 2 cups of milk, while whisking the lumps out. Bring to a gentle boil.
- Once gently boiling, add in the sage, thyme, nutmeg, and a 1/4 tsp salt and 1/4 tsp pepper. Stir to combine. Add in the shredded gruyere cheese and whisk until fully melted. Turn heat off.
Assembling squash lasagna
- In a cast iron skillet, add 1/3 of the cheesy béchamel sauce to coat the bottom of the skillet. Next add a layer of no-boil lasagna noodles, breaking them up to fit the skillet. Spoon a few dollops of the squash purée and spread an even layer to the edges with a spatula. Add some of the caramelized onion and spinach mix over top, then repeat.
- Order of layers: cheesy béchamel sauce, lasagna noodles, squash purée, caramelized onion spinach mix, ending with the last of the cheesy béchamel sauce over the top.
Bake
- Once the squash lasagna is assembled, add a layer of parchment paper, followed by foil over the top. The parchment paper will keep the cheese from sticking to the foil while baking.
- Bake at 400F covered for 20 minutes, then uncovered for 15 minutes until the top layer is golden and bubbly.
- Remove from oven and allow to cool for 5 minutes before serving. Since it is a skillet lasagna, you can serve like a pie or cut into squares. Enjoy!
Notes
*See in-post for step-by-step photos of all elements to recipe*
Making ahead of time:
This squash lasagna can be made ahead of time prior to assembly or after fully assembled.- If making individual elements ahead of time, cheesy béchamel sauce will have to be reheated prior to using.
- If assembling fully and refrigerating, you may need to bake covered an additional 5-10 minutes since all the elements will be colder.