it varies, the pot is important to. I grow 4 types of "keepers" (main crop spuds that you leave in the soil for two weeks after the plant dies, this make the skin thick) I usually pick King Edwards to do this with, just leave them a few weeks or until they feel spongy and look like Rupert Murdoch's face.
Maury's Beef Strog
I have a good cheap supply of Fillet steak tails and off cuts.
Part freeze your steak so you can cut it into 1/4" batons, dredge in seasoned corn starch.
Cut onions and portobello mushrooms into the same size as the meat.
Sweat the onions in a little oil till opaque then tip out of the pan onto a plate.
Clean the pan and sweat the mushrooms till the have lost all their moisture, tip out onto a plate.
Clean the pan, heat a little oil in the pan till it starts to shimmer (very hot) then stir fry the steak for a minute or so, tip in the onions and mushrooms then add very sour cream, keep the burner on max and in a few seconds the corn starch should have amalgamated with the cream to make a soft omelet finish, check the seasoning and serve with the crisp fries.
The contrast of textures between the soft creamy beef and the crisp fries makes this dish and is traditional. Pasta and rice just dont cut the mustard