1.25kg waxy potatoes
250g cultured unsalted butter (look for European-style at the supermarket), chopped, at room temperature
2 tsp fine salt
1⁄4 tsp ground white pepper
1⁄2 cup pure cream, hot
Preheat oven to 200°C. Put potatoes on an oven tray and roast for 1 1⁄2 hours or until centres are very tender.
Cut potatoes in half, scoop out flesh, discarding skins, and press through a fine sieve into a large bowl. Beat in butter, salt and pepper. Fold in cream. Serve.