Whole wheat flour is full of nutrients and flavour and also adds a little extra fibre to your baked goods. (exsloth.com)
The idea is that the black beans, as well as giving a bit of extra fibre, can reduce the amount of fat in the cake without making it taste less delicious. (tinandthyme.uk)
So you get a little extra fibre and protein with an added energy boost! (crumbtopbaking.com)