Heat oven to 220°C/200°C fan-assisted/Gas Mark 7. Prick the potatoes with a fork, place on a plate and microwave on high (900W) for 6 minutes. Turn the potatoes over and microwave for a further 4 minutes. Transfer the potatoes to a baking sheet and brush with the oil.
Season and place on the top shelf of the oven for 20-25 minutes until the skin is crisp and the flesh is soft. Reduce the temperature to 200°C/180°C fan-assisted/Gas Mark 6 if the potato browns too quickly.
Remove the potatoes from the oven. Halve and scoop out most of the flesh. Roughly mash the flesh in a bowl with the sour cream, milk and 2 tbsp chives. Season and spoon back into the potato skins.
Return to the oven and bake for a further 15 minutes until golden.
Scatter with the remaining chives to serve.
4 medium Rooster potatoes (approx 350g)
1 tsp olive oil
100ml sour cream
2 tbsp semi-skimmed milk
3 tbsp chives, finely chopped
Green salad, to serve