Heat oven to 200C/fan 180C/gas 6. Prick
the potatoes several times with a fork, then
microwave on High for 8-10 mins, turning
once, until tender. Meanwhile, heat the oil
in a non-stick pan, add the mushrooms and
rosemary and cook over a fairly high heat,
stirring, until the mushrooms are tender and
lightly coloured. Season to taste.