Chocolate and sweet potato brownies.

Fudgy Gooey Vegan Brownies

Finally, the long-promised recipe for my sweet potato brownies. It’s been in development for a while but I think (I hope) I’ve finally cracked it. Several attempts ended up more cake than brownie, but I really wanted to get that quintessential rich, fudgy gooeyness you’d expect from a brownie. As with a traditional brownie, the key is not to overbake it. The sweet potatoes really add to the gooey texture, but it’s important that you cook them only to the point that they will give a drier (not soggy) mashed potato. If the potatoes are overcooked they will add to the liquid content of the recipe and you’ll end up with something more cakey.  I haven’t quite figured out the gluten-free version yet, but I’ll update the page as soon as I have. So here goes!


400g sweet potatoes, peeled (I recommend starting with 500g-600g to allow for weight loss after peeling and cooking).
3 tbsp ground flax seed
100g dark chocolate, broken into pieces, plus 50g chopped into small pieces and reserved for later in the recipe
1 tsp vanilla extract
100ml oil (sunflower, rapeseed or coconut*)
100g plain flour
110g sugar
30g cocoa powder
1 tsp bicarbonate soda
1/2 tsp salt
50g hazelnuts, roughly chopped

Gooey Fudgy Brownie Method

  1. Start by peeling the sweet potatoes. Next cut them into chunks, roughly equal in size. Put them into a saucepan, cover with cold water, and bring to the boil. Boil for about 5 minutes before reducing the heat to a simmer. Check the progress of the potatoes by piercing them with a knife. We don’t want to overcook the potatoes (if they yield completely to the knife they’re overdone), so ideally you should be able to cut through the potato and still feel some resistance. When they’re ready, take the pan off the heat and drain off the water.
  2. Put the chocolate pieces into a heatproof glass bowl. Place the bowl on top of the saucepan containing the sweet potatoes and leave the chocolate to melt. There should still be enough heat emanating from the sweet potatoes to melt the chocolate, but alternatively you can place the glass bowl over a small saucepan of simmering water so that the chocolate melts.
  3. While waiting for the chocolate to melt, sift the flour, cocoa powder, bicarbonate of soda and salt into another bowl.
  4. Place the ground flax seed in a small bowl or ramekin dish with two tablespoons of water. Mix with a teaspoon and leave to thicken.
  5. Mash the sweet potato and weigh out 400g. Stir the mashed potato into the melted chocolate (which should be cooled by now) and then the oil, vanilla extract and flax seed. Mix everything together well.
  6. Fold the dry ingredients into the sweet potato mixture. Finally, stir the chocolate chips.
  7. Spoon the mixture into a lined 22cm / 9” square tin (or similar) and scatter over the hazelnuts.
  8. Bake for approximately 20-23 minutes at 180°C. We’re aiming for a gooey, fudgey brownie, so don’t worry that it doesn’t seem ‘done’. Leave it to cool before putting the tin in the fridge to set.

If you can resist the temptation to devour the brownies straight from the fridge I recommend gently reheating in the oven later on and serving with some ice cream or frozen yogurt.

*If using coconut oil, melt before mixing with mashed sweet potato and melted chocolate.

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