1. Peel the potatoes,
wash them,
cut them into large cubes.
2. Peel the leeks,
wash them,
remove almost all of the green part
and cut them into 2 cm long pieces.
3. Melt the butter in a saucepan.
4. When the butter is hot, add the leeks and cook them over low heat without letting them brown.
5. Add water,
add the potatoes.
6. Season and let cook over medium heat for 30 minutes.
7. Add the milk and serve hot over finely sliced stale bread.