Dried potatoes are probably the best invention in quick, easy food prep there is. These are the best, add to boiling water, add milk and BAM! you got yourself some decent mashed potatoes.
If you want to throw on the apron, my Grandmother always said "One large potato per person and one for the pot".
I quarter (skin on) boil to fork tender and mash with butter, add a bit of sour cream and whip to a decent consistency.
Wife is German so we eat a lot of Klosse (knodel/potato balls). That's the density of paste and takes some getting used to but I like it.