> Add far more butter than anyone would think is reasonable. (Like, 1/2lb of butter to 1lb of potatoes. Maybe more.)
No. The butter gets lost in the potatoes and mouthfeel of the fat is compromised. That is the reason that so much is needed if you do it this way. Much better to only add it right when serving, leaving the butter and potatoes largely unmixed. Preferably added in an amount “to-taste” by the individual. I believe this was covered by McGee’s “On Food and Cooking”, but I may be misremembering.
I would buy a cooking book with recipes explained like this one. With real world tricks and explaining "why" you do it in that way. A raw list of ingredients is, in my opinion, almost useless.
America’s Test Kitchen (TV) / Cooks Illustrated (books) will scratch your itch.
My foodie friend and I use a lot of their recipes.
The cool thing is that sometimes you will disagree with their preferences (totally normal), so you can use one of their variants that has the attributes that you want. Or similarly, you can see how changing certain ingredients changes the outcome and personalize your version of the recipe accordingly. It definitely saves some experimental batches.
I’ve found that The New Best Recipe cookbook covers this pretty well for me. They have an introduction to each recipe talking about all the variants they tried, and then there’s a clearly marked recipe section.
Steam some potatoes. (Don't boil them. No one wants watery mash.)
Add far more butter than anyone would think is reasonable. (Like, 1/2lb of butter to 1lb of potatoes. Maybe more.)
Add salt and pepper. (No, more than that. You've under-seasoned them.)
Mash them until they're the consistency you want. (For really smooth mash use an electric hand mixer instead of a masher.)
To make them better still, put lots of wholegrain mustard or garlic in with the butter.