Save Pin The first time I made this casserole, it was supposed to be a quick Tuesday dinner solution using whatever I could find in the fridge. The butternut squash had been sitting on the counter for days, and that half bag of quinoa in the pantry was mocking me. But something magical happened when the sausage hit the pan and the thyme started blooming in the heat.
Last November, my sister came over for dinner completely exhausted from work. I pulled this bubbling dish out of the oven, and she literally sat at the counter eating it straight from the baking dish with the wooden spoon I used to stir it. Now she requests it every time life gets overwhelming.
Ingredients
- 1 medium butternut squash, peeled, seeded, and cut into 1-inch cubes: The sweetness of the squash is what balances the spicy sausage, so do not skip the peeling step because the skin gets tough and unpleasant after baking
- 1 medium onion, diced: Yellow onions work best here because they caramelize beautifully and add depth
- 2 cloves garlic, minced: Fresh garlic makes a difference, but in a pinch, the jarred stuff will not ruin the dish
- 3 cups baby spinach: It looks like a lot when raw, but spinach wilts down to practically nothing, so do not be shy about piling it in
- Fresh parsley, for garnish: Optional, but that pop of green against the golden cheese makes the whole thing look like you tried harder than you actually did
- 1 pound Italian sausage, casing removed: Sweet sausage keeps it family friendly, but spicy kicks it up exactly when you need that extra warmth on a cold night
- 1 cup cooked quinoa: Make extra earlier in the week, or use leftover rice if that is what you have on hand
- 1 cup shredded mozzarella cheese: Low moisture mozzarella melts better and does not make the dish watery
- ½ cup grated Parmesan cheese: The salty funk of Parmesan cuts through the sweetness of the squash
- 2 tablespoons olive oil: Enough to coat the bottom of your pan and help the vegetables cook evenly
- 1 teaspoon dried thyme: Earthy and warm, thyme pairs perfectly with both squash and sausage
- 1 teaspoon dried sage: Sage is the secret ingredient that makes everything taste like fall
- 1 teaspoon paprika: Smoked paprika adds depth, but regular works fine too
- Salt and pepper, to taste: The sausage is already salty, so taste before you go heavy handed here
- 1 cup chicken or vegetable broth: This helps the quinoa absorb flavor and keeps the casserole from drying out in the oven
Instructions
- Get your oven ready:
- Preheat to 375°F and grease a 9x13 inch baking dish while you prep everything else
- Start the aromatics:
- Heat olive oil in a large skillet over medium heat, then cook the diced onion until it turns translucent and soft, about 5 minutes
- Add the garlic:
- Stir in the minced garlic and let it cook for just 1 minute until you can smell it, because burnt garlic gets bitter fast
- Brown the sausage:
- Crank up the heat slightly, add the sausage, and break it apart with a wooden spoon until it is fully cooked through, 7 to 10 minutes
- Season the squash:
- Toss in the butternut squash with the thyme, sage, paprika, salt, and pepper, then cook for 5 to 7 minutes until the squash starts to soften on the edges
- Wilt the spinach:
- Stir in the spinach and cooked quinoa, folding everything together until the spinach has completely wilted into the mixture
- Add the broth:
- Pour in the broth and let it simmer for 3 to 4 minutes so the quinoa can soak up some of that flavor
- Assemble the casserole:
- Transfer everything to your prepared baking dish and spread it evenly before topping with both the mozzarella and Parmesan
- Bake covered:
- Cover the dish with foil and bake for 25 minutes so everything can steam and meld together
- Get the cheese golden:
- Remove the foil and bake for another 15 to 20 minutes until the cheese is bubbling and has those gorgeous browned spots
- Let it rest:
- Wait 5 minutes before serving so the casserole sets up a bit, then sprinkle with fresh parsley if you want it to look pretty
Save Pin This recipe became my go to when my neighbor had her baby, because it reheats perfectly and freezes well. She texted me a month later saying it was the first thing she actually wanted to eat during those exhausting newborn days.
Make It Ahead
You can assemble the entire casserole up to 2 days before baking, just cover it tightly and keep it in the refrigerator. Add about 10 extra minutes to the baking time if it goes into the oven cold from the fridge.
Vegetarian Swap
Plant based sausage works surprisingly well here, or you can use a can of drained and rinsed white beans for protein instead. The spices and squash carry so much flavor that nobody will miss the meat.
Serving Suggestions
A simple green salad with lemon vinaigrette cuts through the richness, and crusty bread is never a bad idea for soaking up any extra juices.
- The leftovers actually taste better the next day
- Pair with a light red wine like Pinot Noir
- Freeze individual portions for easy lunches
Save Pin This is the kind of dinner that makes people feel cared for without you having to say a word.
Recipe FAQs
- → Can I make this casserole ahead of time?
Yes, assemble up to 2 days in advance and refrigerate. Add a few extra minutes to baking time if baking from chilled.
- → What can I substitute for the Italian sausage?
Use plant-based sausage, white beans, or ground turkey for different protein options while maintaining the hearty texture.
- → Is this dish gluten-free?
Yes, if you use certified gluten-free sausage and broth. Quinoa is naturally gluten-free.
- → How do I store leftovers?
Store in an airtight container in the refrigerator for up to 4 days. Reheat in the oven or microwave until warmed through.
- → Can I freeze this casserole?
Yes, freeze before baking for up to 3 months. Thaw overnight in the refrigerator before baking as directed.
- → What wine pairs well with this dish?
A light red wine like Pinot Noir or a crisp white like Sauvignon Blanc complements the savory sausage and sweet squash.