Patatas al alioli (Potatoes in Garlic and oil sauce)

This is a very popular dish, both as a tapa and as an accompaniment to a main course, so now you can make it for yourself.

750g potatoes
Alioli (garlic and oil) sauce
1 tablespoon mild mustard
1 tablespoon sea salt
Table salt
1 pinch of recently crushed pepper.

Peel the potatoes and chop them up into pieces. Cook in water with sea salt until tender but not to the point that they break up. Strain and leave to cool. Mix with the alioli sauce and season to taste. Serve on a plate or in 6 individual dishes.