The best vegan brownie I’ve ever made, these are SO fudgy with a crispy meringue-like top and a gooey centre. Such a delicious way to use up that sourdough discard too!
After people started making my original sourdough brownies recipe from last year, I had a few requests for a vegan version. I knew from past experience of brownie testing that veganising the recipe wouldn’t just be as simple as replacing the eggs with flaxseed. In brownies, the eggs form an essential part of the ‘bulk’, coagulating upon cooking to hold everything together whilst maintaining that key fudginess we all love. In my non-vegan recipe, the eggs are even more essential, providing that crackly top and a light texture.
After some experimentation I came up with a combination of ingredients to replace the eggs:
- Aquafaba: the obvious choice here for that meringue-y effect was aquafaba (i.e. chickpea liquid which can whip up like egg whites). I replaced the majority of the egg volume with whipped up chickpea liquid which gave me the crispy, crackly crust. However, aquafaba doesn’t coagulate on cooking so I needed to turn to some other ingredients for that…
- Ground almonds + cornflour: I initially used some extra flour in the recipe to provide that coagulation/bulk but that made them have a weird claggy texture, almost like a dense chocolate cake rather than a tender brownie. Ground almonds provide bulk whilst giving a moist, fudgy texture. They’re also fatty so provide the missing richness we lose from not having egg yolks. I also added in some cornstarch for that extra coagulation factor – it helps the brownies maintain more stuctural integrity once cooled but it is optional so if you don’t have any, they’ll still work.
- Baking soda: the last aspect the eggs provide is LIFT! We get a lil bit of that from the aquafaba but, as the aquafaba doesn’t set, we need something else to just give a slight bit of rise to the brownies. Good old baking soda to the rescue! It reacts with the acidity of the sourdough discard in the batter.
I would say these are still different to the original brownies as they’re more fudgy and less moussey BUT they are INCREDIBLY good brownies. I think if I had been given one and didn’t know they were vegan, I wouldn’t be able to tell. Part of this is kind of down to the fact there’s not GODDAMN FLAXSEED or CHIA SEED getting stuck in my teeth when I eat them! hahaha.
Other vegan sourdough discard recipes:
NB: I’ve provided DETAILED ingredient notes below the recipe. I recommend reading through the recipe & reading the notes before you start, just so you have all the info. There are substitution notes too for if you don’t have some of the ingredients but if your Q isn’t answered there, please leave a comment/DM me/ Email me and I’ll get back to you ASAP.
- 120g (1/2 cup) aquafaba (chickpea/black bean/kidney bean water) (see notes)
- 1/4 tsp cream of tartar, optional
- 250g (1 cup + 2 tbsp) caster sugar (i.e. superfine sugar) or granulated sugar
- 100g (7 tbsp) vegan block 'butter' (75% fat content minimum)
- 150g (5.3 ounces) dark chocolate (60-70% cocoa content), broken into small chunks
- 200g (1 cup) sourdough discard, 100% hydration
- 1 tsp vanilla extract
- 50g (1/2 cup) unsweetened cocoa powder, I used Guittard cocoa rouge
- 70g (3/4 cup) ground almonds (almond flour)
- 30g (3 tbsp) cornflour (cornstarch), optional (see notes)
- 1/4 tsp bicarbonate of soda (baking soda)
- 1/4 tsp fine table salt
- flaky salt, for sprinkling (optional)
Whisk the aquafaba:
- Place the aquafaba and cream of tartar (if using) in the bowl of a stand mixer fitted with the whisk attachment (or in a large bowl, if using a handheld electric whisk). Whisk on high speed until it becomes a thick pale foam, like whipped egg whites.
- Whilst continuing to whisk, add the sugar a few tablespoons at a time.
- Once all the sugar has been added, continue to whisk for 5 minutes more to ensure as much sugar as possible has dissolved. The mixture will still feel slightly grainy if you rub some of it between your fingertips (if it feels VERY grainy, keep whisking to allow more of the sugar to dissolve). It should look glossy, thick and opaque white, like egg whites whisked to semi-stiff peaks.
NB: I've noticed that sometimes the aquafaba doesn't get AS thick as egg whites after whisking, i.e. it doesn't hold a peak when the whisk is lifted out. But as long as the mixture is opaque and roughly tripled in volume when you're done whisking, it should be fine to use.
Melt the chocolate & butter:
- Place the vegan butter and broken up chocolate into a small pot and place over a low heat. Stir until almost fully melted. Remove from the heat and set aside so the residual heat can melt it all fully.
- Once fully melted, stir the sourdough discard and vanilla extract into the pot of melted chocolate/butter mixture. It may look kind of split/grainy but this is fine.
Combine & Bake:
- Preheat the oven to 180°C (350°F) fan or 200°C (400°F) non-fan. Line a 7.5 x 9.75-inch (19 x 25 cm) rectangular OR an 8 or 9-inch (20 or 23cm) square brownie pan with baking paper.
- Mix around 1/4 of the whisked aquafaba into the melted chocolate mixture. You don't have to be gentle here as this step is to help loosen the texture of the chocolatey mixture.
- Now pour that loosened chocolatey mixture into the bowl of whisked aquafaba. Sift the cocoa powder, ground almonds, cornflour, bicarb and salt on top (see notes if you don't have a sieve).
- Use a silicone spatula to fold the mixture together gently, trying to maintain as much of that air in there as possible. Make sure you get right to the bottom of the bowl and scrape the sides too!
- Pour the batter into the prepared pan and bake for 25-30 minutes - the top should look dry, matte and the brownies shouldn't wobble when you shake the pan. If you insert a toothpick into the centre, it should come out with some thick, gooey batter (NOT loose, drippy batter!) attached to it.
- Remove from the oven and run a knife around the edges whilst they're hot to loosen any bits which may be stuck. Leave to cool for 20-30 minutes before removing from the tray and cutting into squares. They will sink in the centre as they cool so may crack a bit as this happens. You can sprinkle them with some flaky salt as well now.
Aquafaba: This is the liquid from a can of cooked beans. I tested these brownies with the liquid from can of chickpeas and black beans (Sainsbury's own brand). Both worked great. I like to make sure I shake the can a lot before I open it & drain off the aquafaba which helps to dislodge the sediment from the bottom of the can (which I believe helps the aquafaba to whip up more reliably). If your aquafaba isn't whisking up properly, try reducing it over a low heat until halved in volume before measuring and using in the recipe. Also, note that aquafaba definitely takes longer to whisk into a stiff foam than egg whites do, so give it some time!!! A stand mixer is the best option here as the extra power makes it whip up in no time whereas my experience using hand-held whisks is that it takes longer to reach the right consistency.
Cream of tartar: I add this to help stabilise the aquafaba foam which, in the end, leads to slightly less sunken brownies. However, I've tested it multiple times without COT and they're just as good, probably just a bit fudgier in the end.
Caster/ superfine sugar: golden caster sugar works here as well as white caster sugar. If you can't get this, try blitzing granulated sugar in a food processor or blender until fine (let it settle before removing the lid!). Likewise, powdered sugar (icing sugar) works - just make sure you're using the same weight (so if you're measuring by volume you'll need to adjust the number of cups). Otherwise, just use granulated sugar - this means you'll probably have to whip the mixture for longer and you may not get as fine a texture.
Vegan butter: I used Naturli vegan block (from Sainsbury's in the UK) which is a solid block 'butter' with a fat content of 75%. DO NOT use a low fat margarine here!
Vegan dark chocolate: I used a Guittard 70% chocolate here but Pico is also a great brand of vegan chocolate to use. Otherwise, check the packet of your chocolate to ensure it's vegan - most dark chocolates around 70% cocoa content already are dairy-free.
Sourdough discard: This isn't leavening the brownies so it does not need to be active. I save my discard in the fridge in a lidded container for a week or two and then use it for baking. 100% hydration means that your sourdough is fed with equal weights of water and flour. My sourdough starter is 50:50 rye and white wheat flour but an all white starter, or a 50:50 white/wholemeal wheat flour starter will also work.
Ground Almonds: Other good substitutes are ground hazelnuts or ground cashews. If you can't do nuts, try ground sunflower seeds. You can make your own by pulsing nuts/seeds in a food processor or blender until mealy.
Cornflour: These do work without the cornflour in them but they will be a bit softer and more fragile. The cornstarch just helps bind things together a bit better but if you don't have any, they will still work out.
No sieve: instead, combine the cocoa powder, ground almonds, cornflour, bicarb and salt in a small bowl. Stir together with a whisk or a fork to remove any lumps.