Wash and tail beans. Please note that you could use more; the quantity doesn't matter.
If you're cooking for more than 4 people, use more beans and maybe 2 potatoes.
Cut the beans cross-wise into rounds -- anything from thinly sliced to 1" long.
Carry on until all the beans have been cut.
Put in a pot, and slice the peeled potato and onion over the beans.
Add about 1/3 cup water, sugar, white pepper and salt.(Yes, white pepper is the best here, but black pepper is fine).
Don't mix: just put lid on and bring to boil, then lower heat and let simmer.
Bring to the boil, lower heat, put lid on, and let the whole lot simmer until everything is very soft.
Using one of your utensils, which you use to mash any vegetable roughly, mash the beans, potato and onion, but don't try to beat it to a pulp -- there should be texture left.
Usually there is a bit too much liquid left. Drain this off -- I use a sieve -- or you can boil it away over high heat, but be careful not to burn the veggies.
Add a good knob of real butter, fork through, and sprinkle with nutmeg to serve.
This simple dish can easily be made ahead and warmed up -- the flavour improves.
Serve as a vegetable side dish.