I love my mashed potatoes but it was not until I was living in London that I began adding more to create a mashed veg instead of just mashed potatoes.
Simple easy and something a bit different and healthy too...if you watch the butter and salt :)...
Potatoes - try some new potatoes with skin on!
Swede - my absolute favorite - called Swede (aka Swedish Turnip) in the UK and Rutebegas in the US
Carrot - just for some color!
Jerusalem Artichoke - these are not your average artichoke
Boil and then mash ALL together with some liberal butter and salt and a little EVOO if needed...Personally, I use a hand masher so that it stays chunky and presents with great texture!