Step 1

1. Preheat the oven to 220°C (425°F/Gas 7). Using some of the melted butter, grease a 12-hole standard muffin tin.

Step 2

2. Cook the potatoes in a saucepan of boiling salted water for 7 minutes, or until just tender. Drain thoroughly.

Step 3

3. Grate the potatoes and onion into a bowl and pour the melted butter over. Season with sea salt and mix together well. Using two forks, divide the mixture among the muffin holes, gently pressing it in. Bake for 45 minutes, or until golden.

Step 4

4. Run a small palette knife around each rösti to loosen them. Serve hot.