Florencia Baldini Last Updated on October 8, 2025This butternut squash pasta sauce is next-level creamy, and I can’t wait for you to try it! With just five simple, wholesome ingredients, you can create a golden, velvety sauce that transforms any pasta dish into a cosy, comforting meal.
If you’ve never thought of using butternut squash for pasta sauce, now is the time to give it a go. Roasting the squash brings out its natural sweetness, and when blended with onion, garlic, cashews, and a touch of nutritional yeast (or cheese), it becomes luxuriously smooth and creamy. This sauce has all the warmth of autumn with its seasonal flavours, and it’s completely dairy-free – the perfect alternative to creamy, dairy-based pasta sauces.
Cheese Vs Nutritional Yeast – Your Flavour Choice
Nutritional yeast: You can choose whether to make this sauce with nutritional yeast or cheese. If you’re looking for a vegan version, or simply want to try a new ingredient, I really recommend nutritional yeast. It’s packed with B vitamins, adds protein and fibre, and has a naturally nutty, cheesy flavour that works beautifully in creamy sauces. I used a brand called ‘Bosh‘ here in the UK, but you should be able to find it easily in most supermarkets these days, usually in the free-from section.
Cheddar or Parmesan cheese: If you don’t have any dietary requirements and want even more depth of flavour, go with cheese — parmesan and cheddar are my favourite choices. Parmesan brings that salty, savoury richness that clings to the pasta, while cheddar melts in for extra creaminess and a stronger taste.
Step-By-Step Instructions
Step 1 – Place the chopped butternut squash and onions on a large baking tray. Step 2 – Drizzle with olive oil, season with salt to taste, and toss with your hands until evenly coated. 
Step 3 – Wrap the onion into foil. Bake the vegetables. Step 4 – Add the roasted vegetables and the rest of the ingredients in a blender. Step 5 – Blend until smooth. Step 6 – Pour the sauce over the pasta and toss until evenly coated.
Tips
- Soak the cashews if you don’t have a high-speed blender – just 15–20 minutes in hot water will make them blend into a super creamy sauce.
- Wrap garlic and onion in foil before roasting – this keeps them from burning while the squash caramelises beautifully.
- Chop the squash small so it roasts quicker and gets soft all the way through.
- Blend while hot – warm ingredients blend more smoothly into a silky sauce.
- Taste before serving – add a little extra salt, lemon juice, or even a splash of pasta water if needed to loosen the sauce.
- Make ahead – the sauce keeps well in the fridge for 3–4 days, so it’s perfect for meal prep.
Swaps
Butternut squash: Pumpkin or sweet potato work really well too – both bring that natural sweetness and creamy texture, you might need to
Cashew nuts: For a nut-free option, try sunflower seeds. Or go for 2–3 tablespoons of tahini for a richer flavour.
Nutritional yeast: Grated Parmesan or pecorino will make it cheesier if you’re not keeping it dairy-free.
Onion: Shallots or even leeks are great alternatives – they add a lovely gentle sweetness.
Garlic: Short on time? Garlic powder works too. Start with ½ tsp and adjust to taste.
Storage
Fridge: Keep the sauce in an airtight container in the fridge for up to 2-3 days – just make sure it hasn’t been mixed with pasta yet. Once combined, it’s best enjoyed straight away or within a day, as the pasta will soak up the sauce and change the texture. For the creamiest result, store the sauce on its own and mix with freshly cooked pasta when ready to eat.
More Butternut Squash Recipes
- Kale&butternut squash cous cous
- Thai Butternut Squash Soup
- Parmesan Squash Chips
- One-Tray Lentil & Roasted Vegetable Salad
Butternut Squash Pasta Sauce
Video
Ingredients
- ½ butternut squash, 450-500g peeled & deseeded flesh, chopped into cubes
- 1 yellow onion
- 5 garlic cloves
- 2 tbsp nutritional yeast, you can swap with cheese
- 60 g cashew nuts
- oil, salt, pepper , to taste
- 200 g pasta
Instructions
- Chop the butternut squash, onion, and garlic. Place on a tray, drizzle the oil and add salt and pepper to taste.
- Roast at 180°C (350°F) for about 30 minutes. Tip: wrap the garlic and onion in foil so they cook gently and don’t burn while the squash roasts.
- Meanwhile, cook your favourite pasta.
- Once the vegetables are ready, put all the ingredients into the blender a blend until silky and smooth.
- Pour the sauce over the cooked pasta and mix to coat.
Notes
- This golden sauce is naturally creamy thanks to cashews and roasted butternut squash — no dairy or cream needed.
- Nutritional yeast adds a cheesy, nutty flavour, but you can swap it for parmesan or pecorino if you prefer.
- The sauce pairs beautifully with most pasta shapes — from short ones like rigatoni, fusilli or penne that catch the sauce in every bite, to long strands like spaghetti that get coated evenly.
- Roast the garlic and onion wrapped in foil so they soften slowly without burning, adding depth and sweetness to the sauce.