Wash the potatoes and cut them into chunks, leaving the skin on.
Put them into a saucepan and cover with cold water. Bring to the boil then turn the heat down and simmer for 9 minutes or until tender when pricked with a fork.
Add the peas and cook for another minute.
Drain and roughly crush the potatoes and peas together with a fork, adding a generous pinch of salt, a grind of black pepper and the olive oil.