Potatoes with buttermilk used to be a typical winter supper on the farm where my friend Maryvonne grew up (in Brittany, Franc). Everyone would help themselves to the potatoes in a big bowl in the center of the table, then they would pour buttermilk over the top, and mash everything together (with butter from the farm) for a one-dish meal. Meat, poultry, and seafood dishes were always reserved for weekends and special occasions.

You might not think of nori as traditionally French, but the seaweed can be found on rocks along the coast and has been cultivated on seaweed farms around Brittany for decades. I can now find bags of nori flakes at most local grocery stores. The flakes are convenient, but you can also just finely chop a few nori sheets and add them to the mashed potatoes.

This recipe is paired with Monkfish à l'Armoricaine in "A Menu From My Cancale Kitchen." 

Serves 6

  • 2 pounds small russet or Yukon gold potatoes, peeled
  • Kosher salt
  • 4 tablespoons butter (cut into pieces), plus more for garnish
  • ½ cup buttermilk
  • 3 tablespoons nori flakes or chopped nori


1. Cook the whole potatoes in a large pot of boiling, salted water 25 to 30 minutes, or until tender. Drain, reserving the cooking water.

2. Return the potatoes to the pot and mash with the butter and ¼ cup of the cooking water until smooth. (Don’t over-mash.) Stir in the buttermilk and the nori, and season with salt and pepper. Taste, and add a little more buttermilk if the potatoes seem too dry.

3. Cover and let stand 5 minutes before serving so the flavors can develop. Serve with an extra dollop of butter on top.