This is one of my favourites for anyone who likes mashed potato but is short of time/energy and it's quite frugal too. Just don't knock it unless you try it!
I buy boxes of Mr Mash instant mashed potato.
I confess, I would have shuddered at the thought a while back but it really does taste homemade (nothing like the powdery gloop from Smash).
It doesn't even have any salt in it so you add your own, along with some milk, boiling water and a knob of butter.
3 sachets to a box (2 generous portions per sachet) and it normally cost me £1 a box.
I use it for last minute mash, with chees and a dollop of branston for a snack and it's also good for thickening soups (or a quick leek & potato).