800g potatoes, peeled and cut into chunks
1tsp olive oil
1tbsp mustard seeds
Place potatoes in a saucepan and cover with water.
Bring to the boil and then simmer for 15-20 minutes until they fall off the knife.
Drain and leave in the pan for a few minutes.
Place in ricer a few at a time and collect in a bowl (or use a masher).
Heat the oil and cook for a minute or so until the seeds start to pop.
Add the butter and milk, stirring until the butter melts.
Put the potato back in the pan, over a very low heat. Mix in the milk mixture.