Sourdough discard crackers are the easiest way to use up leftover starter. You whisk 200 g discard with 30 g olive oil and a pinch of fine salt, spread it thin on greaseproof paper, sprinkle with seeds or herbs, and bake at 160°C fan for 25 minutes. Crisp, tangy, and gone within an hour. The cracker is at its best with week-old discard from the fridge — the longer it sat, the sharper the flavour.
The 5-ingredient recipe (UK ingredients)
Sourdough Discard Crackers
Prep5 min
Bake25 min
Yield~60 crackers
Best withWeek-old discard
Ingredients
- 200 g sourdough discard (week-old from the fridge is best)
- 30 g olive oil (any decent extra virgin — Filippo Berio is our everyday)
- ½ tsp fine sea salt
- 2 tbsp seeds, herbs, or grated cheese — your topping
- Pinch flaky Maldon to finish
What you need (200 g discard, 30 g oil, salt, seeds, your topping)
Five ingredients, no flour to add, no rolling pin needed. The discard is the dough.
UK pantry substitutes — what to reach for at Sainsbury's, Tesco or Aldi
| If you don't have… | Use… | UK shop / price |
|---|---|---|
| Extra virgin olive oil | Cold-pressed British rapeseed oil | ~£3 at Tesco |
| Fine sea salt | Table salt (use ¾ the quantity) | Any supermarket |
| Mixed seeds | Sainsbury's mixed seeds 250 g | £1.20 — or Aldi's equivalent £0.79 |
| Smoked paprika | Aldi's own (or pimentón de la Vera at Waitrose if you have it) | £0.89 / £3 |
The method, start to finish
How do you make sourdough discard crackers?
Sourdough discard crackers come together in five minutes. Whisk 200 g of sourdough discard, 30 g of olive oil and ½ tsp of fine salt in a bowl until smooth. Spread the mixture on a lined baking tray to 1–2 mm thick, scatter seeds or herbs over the top, score lightly into squares, and bake at 160°C fan for 22–28 minutes until evenly golden. Cool completely on the tray — they crisp as they cool.
Mixing — 30 seconds, no kneading
Tip the 200 g of discard into a small bowl. Add the oil and salt. Whisk with a fork until smooth and glossy — about 30 seconds. That's it. No resting, no kneading. The discard has done all the fermenting work for you.
Spreading thin — the offset-spatula trick
Line a large baking tray (roughly 30 × 40 cm) with greaseproof paper. Dollop the mixture in the centre. Use an offset spatula (or the back of a large spoon) to spread it out from the centre to the edges in a thin, even sheet. You want 1–2 mm thick — almost see-through in the thinnest patches. Don't worry about the edges being scraggly; trim them or leave them as rustic shards.
Scoring before the bake (so they snap cleanly)
Scatter your topping over the surface and press lightly so it sticks. Then, with a pizza cutter or sharp knife, score lightly into squares (3–4 cm each) — just the surface, not all the way through. The score lines are what let you snap the crackers cleanly after baking. A finger-pinch of flaky salt to finish.
Bake at 160°C fan for 25 minutes
What temperature do you bake sourdough crackers at?
Bake sourdough discard crackers at 160°C fan (180°C conventional) for 22–28 minutes. Lower-and-slow is the secret: a hotter oven browns the edges before the middle dries. Rotate the tray halfway through. They're done when the whole sheet is an even pale gold and feels firm in the centre — not still soft and pliable. They crisp up further as they cool on the tray.
Three UK variations — herb, seeded and cheese
Once you've made it once, the variations are where the fun starts.
Variations Selector
Herb crackers (rosemary, thyme, sea salt)
A small handful of finely chopped rosemary, a pinch of thyme leaves, and Maldon on top. The smell, twenty minutes in, is what gets the rest of the house into the kitchen.
Seeded crackers (Sainsbury's mixed seeds, sesame, nigella)
Two tablespoons of mixed seeds — sunflower, pumpkin, sesame, linseed. We swear by the Sainsbury's mixed seed pack for £1.20. Toast the seeds in a dry pan for one minute first if you want a deeper flavour; press them in firmly before scoring so they don't roll off.
Cheese crackers (mature cheddar, Lancashire, Cornish Yarg)
Grate 40 g of mature cheddar — Davidstow's vintage is our favourite for the sharpness it brings out of the discard. Or use crumbly Lancashire for a softer cracker, or grated Cornish Yarg for the gentle nettle note. Scatter it across the surface, sprinkle a little cracked black pepper, and bake as normal. The cheese melts into the cracker so it's threaded through, not sitting on top.
How thin is thin enough? (the millimetre guide)
How thin should sourdough crackers be?
Sourdough discard crackers want to be 1–2 mm thick. At 1 mm they shatter when you snap them — best for dipping. At 2 mm they're sturdier and biscuit-like — best for cheese. Anything thicker than 3 mm bakes unevenly: brown at the edges, soft in the middle. Spread the mixture as if you're icing a cake, then lift the paper to check you can almost see through the thinnest patches.
Thickness Visualiser
Pick a thickness and we'll show you the cross-section and the bake.
Show the data as a table
| Thickness | Bake time | Crisp level | Best for |
|---|---|---|---|
| 1 mm | 22 min | Shatter-snap | Dipping in hummus |
| 2 mm | 26 min | Crisp-sturdy | The everyday cracker |
| 3 mm | 30 min | Biscuity | Cheese boards |
| 5 mm | uneven — don't | Bends, doesn't snap | Don't |
1 mm — crisp, brittle, shatter-snap
Almost translucent when raw. Bakes in 22 minutes. Snaps with a sharp crack, splinters slightly. Best for dipping in hummus or soft cheese.
2 mm — sturdy, the everyday cracker
Our default. Bakes in 26 minutes. Holds a slice of mature cheddar without breaking. The biscuit you bring out when guests drop by.
3 mm — biscuity, holds dip well
A bit more substantial. Bakes in 30 minutes — the edges will be deeper-coloured than the centre but should still be the right side of golden. Use this thickness if you're making the cheese variation.
Don't go past 3 mm. Anything thicker bakes unevenly: brown crust, pale soft middle. Worse, the cracker bends rather than snaps.
Discard age and cracker flavour
Discard-age-to-cracker-flavour map
Days 0–2
Mild, almost sweet. Sweet-cracker territory.
Days 3–6
Tangy yoghurt. Herb crackers.
Days 7–10
Sharp, vinegary. The sweet spot — cheese crackers.
Days 10–14
Funky, complex. Strong cheese, cured meats.
Day 14+
Vinegary. Use only if it still smells alcoholic-fruity, not rotten.
The lactic-vs-acetic acid balance shifts steadily in fridge storage, which is why old discard makes the best crackers.
Storage and serving
How long do sourdough discard crackers keep?
Sourdough discard crackers keep for 2 weeks in a biscuit tin at room temperature. The crispness fades faster in plastic — store them in metal or glass with a tight lid. If they soften, dry them out on a tray at 140°C fan for 5 minutes and cool completely; they'll snap again. They don't freeze well — the texture goes glassy. Bake fresh every week, since you'll have the discard anyway.
Cooling — why they crisp up after the oven
Crackers go from soft-pliable to crisp-snappable as they cool. Don't pull one off the tray to test it warm — it'll be chewy and you'll panic-bake longer. Cool the whole tray for 30 minutes, then test.
Storing in a biscuit tin (not Tupperware)
Once fully cool, snap along the score lines and pile into an old biscuit tin or a glass jar with a metal lid. Plastic tubs trap residual moisture and soften the crackers within a day.
Clara: "We've made these every Friday for three months. They don't last past 7 pm."
Reviving stale crackers in the oven
If they soften, lay them on a tray and pop them in a 140°C fan oven for 5 minutes. Cool fully — they'll snap again. The cracker is a forgiving creature.
Troubleshooting — soggy, too brown, not crispy enough
Mine came out chewy in the middle
You spread them too thick, or you pulled them out too early. Cool the whole tray completely before judging — they crisp as they cool. If still chewy after a full cool, slide the tray back in at 150°C fan for 5 minutes.
The edges burned before the middle baked
Two likely causes. (1) Oven is too hot — drop to 150°C fan and add 5 minutes. (2) You spread them unevenly with thin edges and a thick middle — work the spatula to even up the thickness before baking.
They softened overnight
Air got in. Most likely the lid wasn't tight, or you stored them in plastic. Revive at 140°C fan for 5 minutes. Next batch, use a metal tin and check the seal.
What to serve them with (UK cheeses and chutneys)
Our favourite pairings, after a winter of trying:
- Lancashire (crumbly, lemony) + Tracklements onion marmalade. The herb crackers are best here.
- Cornish Yarg (mild, mushroomy under the nettle rind) + Bramley apple chutney. Seeded crackers complement the nettle.
- Mature Davidstow cheddar + Branston pickle (the proper, not the small chunk). Cheese crackers — yes, double-cheese is fine.
- Soft goat's cheese (Capricorn, Rosary) + fig jam. Plain crackers — let the cheese sing.
A glass of something cold — we lean toward an English sparkling (Camel Valley, Nyetimber) on a Friday — and that's a Sunday-night supper sorted.
Frequently asked questions
How do you make sourdough discard crackers?
Sourdough discard crackers come together in five minutes. Whisk 200 g of sourdough discard, 30 g of olive oil and ½ tsp of fine salt in a bowl until smooth. Spread the mixture on a lined baking tray to 1–2 mm thick, scatter seeds or herbs over the top, score lightly into squares, and bake at 160°C fan for 22–28 minutes until evenly golden. Cool completely on the tray — they crisp as they cool.
How thin should sourdough crackers be?
Sourdough discard crackers want to be 1–2 mm thick. At 1 mm they shatter when you snap them — best for dipping. At 2 mm they're sturdier and biscuit-like — best for cheese. Anything thicker than 3 mm bakes unevenly: brown at the edges, soft in the middle. Spread the mixture as if you're icing a cake, then lift the paper to check you can almost see through the thinnest patches.
How long do sourdough discard crackers keep?
Sourdough discard crackers keep for 2 weeks in a biscuit tin at room temperature. The crispness fades faster in plastic — store them in metal or glass with a tight lid. If they soften, dry them out on a tray at 140°C fan for 5 minutes and cool completely; they'll snap again. They don't freeze well — the texture goes glassy. Bake fresh every week, since you'll have the discard anyway.
What temperature do you bake sourdough crackers at?
Bake sourdough discard crackers at 160°C fan (180°C conventional) for 22–28 minutes. Lower-and-slow is the secret: a hotter oven browns the edges before the middle dries. Rotate the tray halfway through. They're done when the whole sheet is an even pale gold and feels firm in the centre — not still soft and pliable. They crisp up further as they cool on the tray.
Can I use fresh starter instead of discard?
Yes, but you'll lose the tangy edge that makes these crackers distinctive. Fresh starter (peaked, less than 12 hours old) produces a milder, sweeter cracker — fine but flatter in flavour. Week-old discard is the sweet spot.
Why didn't my crackers crisp up?
Most likely you spread them too thick (over 3 mm), or you pulled them out before the middle was dry. The bake-time rule: ≤2 mm = 22–26 min, 3 mm = 30 min, and they keep crisping for 20–30 minutes as they cool. Don't test crispness on a warm cracker.
What's next
If you've got more discard than you know what to do with, our full collection of UK sourdough discard recipes has 24 more. If you're not sure how old your discard is, how long discard keeps in the fridge is the article to read next. New to discard altogether? Start with a beginner's guide to using your discard — same kitchen, gentler pace.
