On a cold day in February (2013), we strolled down 58th Street in NYC, and walked into the Four Seasons Hotel to get out of the cold for a few minutes.  We walked to the back of the hotel to see what was happening at one of our favorite restaurants, only to find that Joel Robuchon’s L’Atelier was closed.  We had one of our most memorable meals at L’Atelier, ranking on our all time top ten (a very hard list to make).  We loved the mix of French style service with Asian influenced flavors, albeit one of the most expensive meals on our list.  There was an amazing eel “napoleon,” a fois gras stuffed quail, and a passion fruit soup that we’ll never forget.  As a homage to this magnificent restaurant, here is our version of the super-rich mashed potatoes that is a signature dish of Chef Robuchon, potatoes that are like pudding.

Ingredients
– 1 lb Ratte potatoes (can also use fingerlings or Yukon Gold potatoes)
– 1/2 lb unsalted high quality butter
– 1/2 to 3/4 cup hot milk
– Salt to taste
You will need a potato ricer, and a chinois or tamis to make this recipe.  It’s a lot of work, but well worth the effort on special occasions.
1. Scrub the potatoes, but do  not peel. Add enough cold water to cover the potatoes, about one inch above the last layer. For each quart of water add 1/2 tablespoon of salt. Simmer uncovered over moderate heat for 20-30 minutes or until a knife can easily be inserted and removed. As soon as the potatoes are done remove and drain. Do not allow them to sit in the water.
2. Once potatoes are cool enough to handle, but still hot, peel and discard the skins. Half or quarter the potatoes (depending on the size), and pass them through the small grid of a potato ricer into a medium heavy bottomed saucepan.
3.  Place the pan over low heat and using a wooden spatula stir the potatoes to dry them out (approximately 4-5 minutes). Begin adding 3/4 of the butter, little by little while vigorously stirring until the butter is incorporated. This should be done in a similar manner as one prepares any butter emulsion (starting off with a very small amount of butter to start the emulsion).
4. Slowly add the milk in a thin stream (a little at a time) till the desired consistency is reached. The amount of milk will depend on the type of potatoes used, the amount of butter used, and personal taste. Stir vigorously till all the milk is incorporated.Then stir the puree with a whisk to incorporate air and make the puree fluffy.
5. Pass the puree through the chinois or tamis, which is critical to achieve the proper texture.  Don’t skimp on this step.  Depending on your patience, this can be repeated 2 or 3 times for to make the puree silky smooth. Rumor has it that Chef Robuchon demands repeating 5 times at his restaurants.

6. Taste for seasoning. If not using immediately, place the puree in the top of a double boiler over simmering water. Whisk occasionally to keep smooth. The puree can be further adjusted with hot milk or butter before serving.
The best version of this recipe I’ve seen on line is at GreenMarketRecipes.  They have some great pictures.