Sourdough Cake (Moist, Tangy, UK Discard Recipe)

Most discard cake recipes online are mediocre — sponges that work technically, taste fine, but aren't cakes you'd actively choose to eat. This is different. A proper sourdough discard cake — moist, deeply flavoured, just-tangy enough that you notice it without it dominating, with the texture of a really good shop-bought celebration cake. The chocolate-orange version is the one that converts everyone, but the recipe forms a base for at least six variations.

The base recipe

Ingredient	Weight
Sourdough discard (unfed)	200g
Plain flour	200g
Caster sugar	200g
Soft unsalted butter	180g
Large eggs	3
Vanilla extract	2 tsp
Baking powder	1.5 tsp
Bicarbonate of soda	0.5 tsp
Fine sea salt	0.5 tsp

Equipment: 23cm round cake tin, lined with baking parchment.

What makes this cake different

Three details elevate this from ordinary discard cake:

1. The fat ratio. 90% butter to flour by weight is unusually high — most recipes go 60–70%. The extra butter gives a French quatre quarts tenderness.
2. Both raising agents. Baking powder for lift, bicarb for reaction with the discard's acidity. The combination produces a more even rise than either alone.
3. The discard is mature. Use discard that's been in the fridge for 4–7 days. Fresh discard doesn't have enough acid to activate the bicarb properly.

Method

1. Cream the butter and sugar

In a large bowl, cream the soft butter and caster sugar with an electric whisk for 4–5 minutes until pale, fluffy, and noticeably lighter in colour. This step matters — it incorporates air that the cake relies on for its rise.

2. Add the eggs

Beat in the eggs one at a time, mixing thoroughly between each. If the mixture looks like it's curdling, add a tablespoon of the flour to bring it back together.

3. Add the discard and vanilla

Whisk in the discard and vanilla until smooth. The mixture will look slightly different — looser, slightly tangy-smelling.

4. Fold in the dry ingredients

Sift the flour, baking powder, bicarbonate, and salt over the wet mixture. Fold in gently with a spatula or large metal spoon — don't beat or you'll knock out the air.

5. Bake

Pour into the prepared tin. Smooth the top. Bake at 175°C (fan) for 35–40 minutes, until a skewer comes out clean and the top is deep golden.

Cool in the tin for 10 minutes, then turn out onto a rack to cool completely before icing.

The cake's natural texture

This cake comes out denser than a Victoria sponge but lighter than a pound cake. Tender, moist, holds together cleanly under a fork, slightly tangy — closer to French gâteau than to British sponge. It cuts beautifully and keeps for 4–5 days, getting better on day two and three as the flavours marry.

The chocolate-orange variation (the showstopper)

This is the version that wins over sceptics. Modify the base recipe:

• Replace 30g of the flour with 30g cocoa powder.
• Add the zest of 2 large unwaxed oranges.
• Add 100g chopped 70% dark chocolate at the end of folding.
• Increase vanilla to 1 tablespoon.

Serve with crème fraîche and a drizzle of orange-flower honey. The combination of dark chocolate, tart discard, fragrant orange, and slight vanilla creaminess is genuinely spectacular. We've served this to people who claim not to like cake and watched them ask for seconds.

Five other variations from the same base

Lemon and poppy seed

Replace vanilla with the zest of 3 lemons. Add 2 tablespoons poppy seeds. Drizzle with a glaze made from icing sugar and lemon juice.

Coffee and walnut

Add 2 tablespoons of strong espresso to the wet ingredients. Fold 100g chopped walnuts in at the end. Top with espresso buttercream.

Apple and cinnamon

Add 1 large eating apple, peeled and finely diced, plus 1.5 teaspoons of ground cinnamon. Mix the apple with a tablespoon of flour first to stop it sinking.

Carrot

Reduce flour to 180g. Add 200g grated carrot, 50g chopped pecans, 1.5 teaspoons mixed spice, half a teaspoon of nutmeg. Top with cream cheese frosting.

Black forest (with cherries)

Same as chocolate-orange but replace the orange zest with 150g of frozen pitted dark cherries (don't defrost — fold in straight from the freezer to stop them bleeding). Layer with whipped cream when serving.

Icing options

Plain — best for the lemon and apple versions

Just a sprinkle of icing sugar over the cooled cake.

Cream cheese frosting — for carrot

200g cream cheese, 100g icing sugar, 1 tsp vanilla. Whisk together. Spread thickly over the cooled cake.

Chocolate ganache — for the chocolate-orange

200g dark chocolate, 200ml double cream. Heat the cream until just steaming, pour over the chopped chocolate, leave 5 minutes, stir to a glossy ganache. Pour over the cake while the ganache is still pourable; it sets as it cools.

Buttercream — for coffee and walnut

200g unsalted butter, 400g icing sugar, 2 tablespoons strong espresso. Beat until fluffy.

Storage

Stored in an airtight tin at room temperature, this cake keeps for 5 days and improves over the first 48 hours. The crumb tightens slightly; the flavours deepen. By day 3 it's at its peak.

Iced cakes (with cream cheese or buttercream) need refrigeration but bring back to room temperature before serving. Ganache-iced cakes can sit at room temperature for 3 days before they need to go in the fridge.

Common problems

Cake sinks in the middle: opened the oven door too early. Don't peek for the first 25 minutes.

Domed top with cracked surface: oven too hot. Drop temperature by 10°C and increase time slightly.

Dense crumb: didn't cream the butter and sugar enough, or used cold eggs. Beat for at least 4 minutes; eggs at room temperature.

Cake tastes too tangy: discard was too old or too acidic. Use discard from 4–7 days, not 14+.

Cake doesn't rise enough: baking powder past its date, or discard too fresh (didn't activate the bicarb).

Why discard works in cakes

Sourdough discard contains live (or recently live) lactic acid bacteria. The acidity reacts with bicarbonate of soda exactly the same way buttermilk does — producing CO₂ that lifts the cake. The mild fermentation flavour adds depth without being overtly tangy. And the slightly fermented flour is more digestible than fresh, giving a slightly lighter texture.

Many traditional cake recipes from before commercial baking powder existed (such as Welsh cakes, soda bread, and various scones) used buttermilk for exactly this reason. Sourdough discard is, in cake terms, an upgraded buttermilk.

FAQ

Can I use fed starter instead of discard?

Yes, but it's a waste of an active starter. Discard is more flavourful in cakes anyway because it's had time to develop tang.

How tangy will the cake taste?

Subtly. With week-old discard, you'll detect a slight acidity that complements the sugar — most people who taste it call it "interesting" rather than "sour". Two-week-old discard pushes into noticeably tangy territory.

Can I make this dairy-free?

Substitute the butter with high-quality plant butter (Naturli or Flora Plant). The texture changes slightly but the cake works.

Can I make this gluten-free?

Substitute with a gluten-free cake flour blend. Note: the discard itself contains gluten, so this isn't suitable for coeliacs.

Why bicarb AND baking powder?

Bicarb reacts with the discard's acidity for fast initial lift. Baking powder provides the second-stage lift in the oven. Together they give a more even rise than either alone.

Can I freeze this cake?

Yes — wrap unfrosted cakes tightly in cling film and foil. Freezes for 3 months. Defrost overnight at room temperature, then frost.

How big a tin do I need?

23cm round, 5cm deep. A 20cm tin works but you'll need to bake longer; a 25cm tin produces a flatter cake and reduces baking time.

Why bake a cake from discard at all?

Because it's the rare instance where the by-product genuinely improves what it's added to. A cake made with discard is moister, more flavourful, and keeps longer than the same recipe made with milk. The acidity from the bacteria tenderises the gluten in the flour, giving a softer crumb. The fermentation contributes depth.

And practically: if you maintain a starter, you produce around 100g of discard a week. Two weeks of discard gives you exactly the right amount for this cake. It uses up something you'd otherwise throw away and produces a cake people will actually request.

Not many recipes hit all three: useful, frugal, genuinely good. This is one.

Make it for an occasion

This cake earns its place at occasions. The chocolate-orange version is a serious birthday cake; the carrot version is what you bring to a friend's house for tea; the apple-cinnamon version sits on the kitchen counter on a winter Sunday and disappears slice by slice across the day.

Bake the chocolate-orange version with a thick chocolate ganache for a child's birthday and they'll never know it has discard in it. Bake the lemon-poppy seed version for an Easter Sunday and it'll be the first thing that finishes. Bake the carrot version with cream cheese frosting in autumn and people will ask for the recipe.

The discard cake on a tray

For an easier traybake version: pour the batter into a 25cm × 18cm tin lined with baking parchment. Bake at 175°C for 28–32 minutes. Cool, slice into 12 squares, ice individually or dust with icing sugar. Easier to transport, easier to portion, exactly the same flavour. The traybake version is what we make for school fairs, work cake days, and bake sales.

Beyond cake: the discard repertoire summary

Once you've nailed the basic cake, the same fundamental principle (fat + sugar + flour + discard + raising agent) gives you a whole family of bakes:

• Brownies — replace half the flour with cocoa, double the chocolate.
• Banana bread — substitute 200g mashed banana for half the discard, reduce sugar.
• Loaf cake — pour into a loaf tin instead of a round tin, bake longer.
• Madeleines — split between madeleine moulds, bake 8 minutes at 200°C.
• Cupcakes — line a muffin tin, bake 18 minutes at 175°C.

The cake is just the beginning. Once the workflow is in your hands, half a dozen other bakes flow from the same starting point.

One last technical note

Cake-making with discard is forgiving. Unlike bread, where small variations make a big difference, cakes tolerate variations well. The discard could be 3 days old or 10 — both work. The butter could be slightly under-creamed — the cake still rises. The flour could be 5g over — irrelevant. This forgiveness is one reason discard cake is such an accessible recipe; it's a project you can complete on autopilot once you've made it twice. Bake for kids' birthdays, last-minute dinner parties, casual Sunday afternoons. The recipe meets you where you are.