The last issue of Gourmet had some advice about which potatoes to use for mashing. I can never remember which ones are best or the advantages of each variety, so this article was definitely a helpful reminder to me. In the end, it essentially depends upon your taste though.
If you like lumpier potatoes or want to make smashed potatoes, red and white boiling potatoes with a smooth, shiny skin can be used. These varieties also tend to absorb garlic and onion flavor well.
If you like light, fluffy, and smooth mashed potatoes with no lumps it is best to choose a baking potato such as a Russet. These potatoes will have a coarser, non-shiny skin. Traditionally this has been the potato of choice for mashed potatoes, and they absorb milk, butter, and salt very well.
The difference between boiling and baking potatoes is the level of moisture and starch. Boiling potatoes have more moisture and less starch and baking potatoes are the other way around with low moisture and high starch. Baking potatoes, therefore, are drier and tend to absorb a lot of butter and milk.
Boiling potatoes with high moisture hold their shape better during cooking, hence the reason they are used for boiling. So if you are boiling potatoes for stews, then high moisture potatoes are a good choice.
With that said, in between the boiling and baking potatoes are the Yukon Golds, which are medium moisture and medium starch. This is a versatile choice and can be used for stews, mashing, smashing and most of your potato needs. I personally use Yukon Golds.
