Ingredients

  • 14 cup champagne vinegar
  • 2 tablespoons mustard seeds
  • 6 tablespoons Dijon mustard
  • 1 tablespoon coriander seed, crushed
  • coarse kosher salt
  • 3 lbs russet potatoes, peeled, cut into 1 1/2-2-inch cubes
  • 6 tablespoons vegetable oil

Method

  • Preheat oven to 425 degrees.
  • Bring vinegar and mustard seeds to boil in small saucepan.
  • Reduce heat; simmer until almost dry, stirring occasionally, about 5 minutes.
  • Transfer to large bowl.Add Dijon mustard and coriander.
  • Season with coarse salt and pepper.
  • Place potatoes in large saucepan; add water to cover by 1"; sprinkle with coarse salt.
  • Boil for 3 minutes.
  • Drain; return to pan.
  • Cook over medium high heat until dry, shaking pan occasionally, 3 minutes.
  • Meanwhile, drizzle 6 tablespoons oil over large rimmed baking sheet.
  • Plac sheet in oven for 10 minutes to heat.
  • Add potatoes to mustard mixture; toss.
  • Spread potatoes on hot baking sheet (oil may splatter).
  • Sprinkle with coarse salt and pepper.
  • Roast for 15 minutes.
  • Turn potatoes; roast until browned and tender, about 15 minutes longer.
  • Season as needed with coarse salt and pepper and serve hot.