Homemade Vegetarian XO Sauce - The Ultimate Zero Waste Condiment

This Homemade Vegetarian XO Sauce turns a pile of leek tops, mushroom stalks and carrot peelings into the most flavour-packed jar in your fridge. It is salty, spicy, deeply savoury and completely addictive, and it costs you almost nothing because you have already paid for everything in it. Spoon it over rice, stir it through noodles, swirl it into eggs, put it on everything. Let's make it!

Why This XO Sauce Works

Traditional XO sauce is a luxury Cantonese condiment built on dried scallops, Chinese sausage and dried shrimp. This version keeps every bit of that flavour and swaps the expensive part for the scraps you were about to bin.

The nori is the secret weapon. Blended in with the mushrooms and veg, it brings the slightly briny, oceanic quality that makes you think there is seafood in there when there isn't.

When I tested it I genuinely couldn't believe there was no dried seafood in it.

It is one of the best things I have ever made from kitchen waste, and I say that as someone who has been cooking professionally for 20 years.

Thirty-five minutes, one pan, and a jar that keeps for weeks and makes everything it touches taste better.

Recipe Details

• Prep Time: 15 minutes
• Cook Time: 20 minutes
• Total Time: 35 minutes
• Makes: 1 x 350g jar
• Difficulty: Easy
• Special Equipment: Food processor

XO sauce gets its incredible depth from slow-cooking finely chopped aromatics in oil until everything is golden, caramelised, and intensely flavoured. The key here is making sure your scraps are processed finely in a food processor before they hit the pan, because you want a rough paste, not big chunks. The nori sheet blended in with the mushrooms and veg is what gives that oceanic quality, and it is the one thing I would not leave out. And be patient with the cooking, because you want everything to cook right down until it is thick, jammy and deeply golden, and that is where all the flavour lives. This is the same thinking behind all my zero waste recipes for kitchen scraps, just taken about as far as it will go.

Ingredients

Scraps and aromatics

• Tops of 1 leek, roughly chopped
• 50g mushroom stalks (or older mushrooms that are drying out)
• 200g mixed vegetable scraps and peelings - carrot peelings, parsnip ends, onion ends, leek tops, whatever you have
• 5 cloves garlic, peeled
• 1 tsp fresh ginger, grated
• 1 dried chilli (or 1 fresh chilli, roughly chopped)
• 1 sheet nori

Oil and seasoning

• 100ml neutral oil (vegetable or sunflower)
• 1 star anise
• 1 tbsp Korean chilli powder (gochugaru)
• 1 tsp Chinese five spice
• 2 tbsp soy sauce
• 1 tbsp fish sauce (leave out or swap for extra soy to make it vegan)

How to Make XO Sauce

1. Blitz the scraps: Add the mushrooms, mixed vegetable scraps and peelings, and the nori sheet to a food processor. Blitz to a rough, finely chopped paste. You don't want it completely smooth, a little texture is good, but everything should be small and even so it cooks properly.
2. Warm the oil: Pour the oil into a wide, heavy-based pan or wok and warm over a medium heat. Add the leek tops and cook, stirring regularly, for 5 to 6 minutes until they are softened and starting to turn golden.
3. Add the aromatics: Add the garlic, grated ginger, dried chilli, and star anise to the pan. Stir well and cook for another 2 minutes until fragrant. Keep the heat at medium, you want everything to gently sizzle and caramelise, not burn.
4. Add the blitzed scraps: Tip in your food-processor paste and stir everything together well. Add the Korean chilli powder and Chinese five spice and mix through.
5. Cook it down: Cook over a medium-low heat for 15 to 20 minutes, stirring regularly, until the mixture has cooked right down and is thick, deep golden, and jammy. This is the step that builds all the flavour, don't rush it.
6. Season and finish: Add the soy sauce and fish sauce, stir through, and cook for another 2 minutes. Taste and adjust seasoning if needed. Remove the star anise.
7. Jar it up: Allow to cool slightly, then decant into a clean 350g jar. Once fully cool, seal and store in the fridge.

Why You'll Love This Recipe

• Scraps into something spectacular: One jar of incredible condiment from things you were about to throw away.
• One jar lasts weeks: Stir fries, noodles, eggs, rice, it improves everything it touches.
• Completely customisable: Use whatever scraps and peelings you have. It will be different every time and delicious every time.
• Easily made vegan: Leave out the fish sauce and it is fully plant based.
• No special shopping: Nothing beyond what you probably already have in the pantry.

Chef's Tips for XO Sauce

Keep a scraps bag in the freezer: The scraps you use will vary every time and that is exactly the point. Add peelings and off-cuts as you cook through the week, and when you have got around 200g you are ready to go.

No starchy scraps: Leave potato and kumara peelings out of the blitz. They turn the texture gluey.

Dry, shrivelled mushrooms are ideal: If yours are past their best, so much the better. They have more concentrated umami than fresh ones.

Don't cut back the oil: It is what preserves the sauce and gives it that classic XO texture, so resist the temptation to reduce it significantly.

Make it as spicy as you like: One tablespoon of gochugaru gives a good kick without being overwhelming. Add more if you want heat, or swap for regular chilli flakes.

Substitutions & Variations

• No leek tops? Use the ends of an onion or a few spring onion roots instead.
• No nori? The sauce will still be delicious, you'll just lose a little of that briny depth. A tiny splash more fish sauce can compensate.
• No Korean chilli powder? Regular chilli flakes or a mild dried chilli powder work well. Start with less and taste as you go.
• Want it vegan? Simply leave out the fish sauce and add an extra tablespoon of soy sauce in its place.
• No Chinese five spice? A small pinch of cinnamon and a little extra star anise gives a similar warm, aromatic quality.

Storage

Best eaten fresh: This sauce is at its absolute best in the first week, but honestly, weeks later it is still great too!

Fridge: Keep the jar sealed in the fridge for up to 3 weeks. The oil layer on top acts as a natural preserve, just make sure you always use a clean spoon when you scoop some out.

Freezer: Freezes well in small portions, and ice cube trays work perfectly for this. Defrost in the fridge overnight before using.

Avoid: Don't store it at room temperature once opened. The sauce is oil-preserved, not shelf-stable, and needs to stay refrigerated.

Frequently Asked Questions

What is XO sauce? XO sauce is a rich, spicy condiment from Hong Kong, traditionally made with dried seafood, cured meats, chilli, garlic, and oil. It is intensely savoury and umami-packed. This version keeps all the flavour but uses vegetable scraps as the base, making it accessible, budget-friendly, and a brilliant way to use up kitchen waste.

What vegetable scraps can you use in XO sauce? Almost any scraps work well here. Carrot peelings, parsnip ends, leek tops, onion ends, mushroom stalks, celery ends, and courgette trimmings are all brilliant. Avoid starchy scraps like potato or kumara peelings, as they can make the texture gluey.

Does vegetarian XO sauce taste like it has seafood in it? Honestly, kind of, in the best possible way. The nori and fish sauce give it a depth and brininess that is very reminiscent of the original.

What do you eat XO sauce with? Everything. Spooned over steamed rice is the simplest and most satisfying way to try it first, and it is superb stirred through simple egg fried rice. After that: stir fries, noodles, fried eggs, roasted vegetables, dumplings, cheese on toast. It improves everything.

Can you double an XO sauce recipe? Absolutely, just double all the ingredients. You will need a larger pan so the paste has room to cook down properly without steaming. The cooking time will be roughly the same, maybe a few minutes longer.

How do you make XO sauce without a food processor? You can chop everything very finely by hand. It will take 10 to 15 minutes of knife work but the result will be just as good. Aim for a very fine mince, almost paste-like, so everything cooks evenly in the oil.

Is XO sauce the same as chilli crisp? They are similar in concept, both being oil-based chilli condiments, but XO sauce has a much more complex, deeply savoury flavour thanks to the umami-rich scraps and aromatics. Think of chilli crisp as the punchy younger sibling.

How long does homemade XO sauce keep? Up to 3 weeks sealed in the fridge, and it freezes well beyond that in small portions. The oil layer on top does the preserving, so keep it topped up and always use a clean, dry spoon.

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This Homemade Vegetarian XO Sauce is the kind of thing that makes you rethink everything you throw away. One jar, made from scraps, delivers weeks of incredible flavour, the sort of deeply savoury, spicy, fragrant condiment that makes even plain rice feel like a proper meal. The nori is the secret weapon, the slow caramelisation is the technique, and the result is something genuinely spectacular from almost nothing. Once you have a jar of this in the fridge, you will never look at your peelings pile the same way again.

Enjoy!

Del x

Salty, spicy, deeply umami, and made entirely from scraps you were about to bin.