Fill a large saucepan with water and a little salt. Bring to the boil.

In the meantime, wash and peel the potatoes. Chop them into equal-sized chunks.

Once the water is boiling, add the potatoes and boil for 15 minutes, or until they are soft (you should be able to insert a knife or fork through one easily).

Drain the water from the potatoes and immediately add the butter and milk. Use a potato masher to mash everything together until smooth. You may need to add a little extra milk if the consistency isn't smooth enough for you.

Optionally grate in some cheese, crushed garlic, extra salt and pepper.