150-250ml milk or UHT cream, or a combination, heated
salt and pepper to taste
Wash the potatoes and place in a saucepan with enough water to cover them, add a teaspoon salt to the water. Bring to boil and lower heat to simmer until tender (easily pierced with a fork). Drain potatoes, peel and mash to the desired texture while hot.
Place the mashed potatoes in a saucepan over low heat for 2-3 minutes to let them dry out, stirring now and then. Remove from heat.
Warm the milk or cream without boiling add the butter and seasoning to the milk, if you like. Then add the hot liquid to the mash, a little at a time, mashing it in, or stir with a wire whisk, until smooth.
For a silky texture, pass the mash through a fine sieve with the help of a pastry scraper while it is still hot.