1kg(2lb)potatoespeeled and cut into 5cm (2-inch) pieces
50g(4tbsp)butter
120ml(½cup)whole milk
120ml(½cup)buttermilk
Fresh chivesminced, for garnish
Instructions
In a large saucepan, cover potatoes with generously salted cool water and set over medium-high heat. Bring to a vigorous simmer and allow to simmer until the potatoes are completely tender when pierced with a fork but not yet breaking down, about 25 minutes. Turn off the heat. Drain and return to pot.
When potatoes are almost finished cooking, add milk and buttermilk to a small saucepan. Over medium-low heat and swirling often, heat the milk mixture until just steaming. Turn off the heat and set aside.
Add the butter to the pot with the potatoes. Using a wooden spoon, crush the potatoes against the sides of the pot until they're broken down and the butter melts.
Pour the buttermilk mixture over the potatoes and stir, gently, continuing to break the potatoes down with the spoon. Season with salt and pepper to taste. Serve garnished with freshly chopped chives, if desired.