‘I developed this recipe for my husband Giancarlo, who has coeliac disease and is also a pre-diabetic with a sweet tooth! The general premise was to provide him with a chocolatey hit to satisfy his sugar cravings, combined with low-GI carbohydrates (the beans and sweet potato) and protein (the walnuts) to slow down the insulin spike.’
I use Total Sweet, made from xylitol, to lower the calories and give a slower release of glucose than conventional sugar.
Black beans, ready-cooked and in tins, are most convenient. But you can buy dried black beans, soak them overnight, then cook them in fresh water the following day. They can take up to 1 hour 30 min to cook, and I usually add 1 tsp bicarbonate of soda towards the end to help soften the skins.
I bake the sweet potato first, then scoop out the flesh. It doesn’t change much in weight after cooking – as a guide a 120g sweet potato will be enough to give you 100g cooked sweet potato.
Katie’s tip: ‘This is a dense, gooey cake that’s best if it’s slightly undercooked (like brownies). The topping is optional and makes it more of an occasion cake. You could bake it in a square tin and cut it into smaller squares, topped simply with a light dusting of cocoa powder to serve with coffee.’
Black bean chocolate mud cake
Prep 15 min Cook 30 min
Cuts into 12 small slices
- 200g cooked black beans
- 100g cooked sweet potato
- 4 eggs, separated
- 75g Green & Blacks Organic Cocoa Powder
- 125g Total Sweet, or use 5 tbsp rice malt syrup or 150g blended
- Medjool dates
- 75g butter or coconut oil
- 1tsp vanilla extract
- 1tsp gluten-free baking powder
- 3–5tbsp milk or dairy-free alternative
- Handful walnuts or raspberries, optional
For the coconut frosting (optional)
- 400g tin full-fat coconut milk (chilled overnight in tin)
- Seeds from 1 vanilla pod or a few drops vanilla extract
- Handful raspberries or walnuts, to decorate
1 Heat the oven to 180ºC/fan 160ºC/gas 6. Line a 20cm diameter cake tin with baking paper.
2 Purée the black beans and sweet potato in a food processor, or mash with a potato masher. Add the egg yolks, cocoa, sweetener, butter/coconut oil, vanilla, baking powder and 3tbsp milk. Blend or mix until smooth. If the batter seems very stiff, add an extra 1–2tbsp milk to loosen it. It should be just soft enough to drop from a spoon.
3 Whisk the egg whites in a separate bowl using an electric mixer until stiff peaks form. Take a large spoonful and stir it into the chocolate mixture. Gently fold in the rest of the beaten egg white, taking care not to knock the air out. If you’re adding walnuts or raspberries, gently fold them in now.
4 Pour the mixture into the prepared cake tin and smooth the surface. Bake for 30 minutes or until the top is set firm but the cake has a slight wobble underneath. Remove from the oven and allow to cool.
5 To make the frosting, carefully spoon the dense coconut cream from the top of the tin into a bowl. (The watery liquid underneath can be kept for smoothies or adding to porridge oats instead of milk.) Add the vanilla and whisk until stiff. Spoon over the cooled cake and decorate with raspberries or walnuts.