A recipe from Philippe Chavent of La Tour Rose in Lyon

1. Peel the potatoes, place them in a saucepan, cover with milk, season with coarse salt and cook over medium heat; drain, reserving the milk. 
2. Take a ladleful of the milk used for cooking; place it in a small saucepan, add 1 tbsp. cream and a pinch of saffron. Bring to a boil and leave to infuse. 
3. Put the potatoes through a food mill. Blend in the hot saffron-infused milk and cream mixture to create a smooth purée.
4. Whisk in the olive oil. Correct the seasoning.