Step 1

Place the potato in a large saucepan of cold water. Bring to the boil over high heat. Simmer for 5 minutes or until slightly tender. Drain. Place, in a single layer, on a tray lined with paper towel. Set aside for 30 minutes to cool.

Step 2

Preheat oven to 180°C. Brush 2 large baking trays with a 1/2 tbs oil. Combine the butter and remaining 1 1/2 tbs oil in a small bowl.

Step 3

Use a fork to scrape the curved side of the potato lengthways. Place, in a single layer, cut-side down, on the prepared trays. Brush with butter mixture. Roast in oven, brushing with the butter mixture once, for 50 minutes or until golden brown. Sprinkle with sea salt to serve.