Jersey royal, onion, sherry and tarragon bake

Method

1. Heat the oven to 220°C/fan200°C/gas 7. Butter a 1.5 litre ovenproof dish. Chop the potatoes into even chunks, then put in a pan of lightly salted cold water and bring to the boil. Cook for 10 minutes or until just tender.
2. Meanwhile, finely slice the onions and chop the tarragon. Toss the potatoes, onions and tarragon in the ovenproof dish. Crush the garlic, then stir into the potatoes along with the fino sherry and double cream. Season.
3. Grate 50g gruyère or vegetarian alternative and sprinkle over the top, along with the breadcrumbs. Bake in the oven for 25 minutes or until the top is golden and crisp.