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Mashed Potato Casserole with Fontina and Sage

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Potato Type: Russet
Cuisine: American
Prep Method: Baked


Side Dish


  • 8 tablespoons unsalted butter, at room temperature, plus more for greasing or use avocado cooking spray
  • 3 lbs. baking potatoes, peeled and cut into 2-inch pieces
  • 1/2 cup sour cream (4 ounces)
  • 2 tablespoons finely chopped parsley
  • 1 tablespoon finely chopped sage
  • 8 ounces imported Fontina cheese, shredded
  • 4 ounces grated gruyere or sharp white cheddar cheese
  • Kosher or Sea Salt
  • White Pepper
  • 1/3 cup plain dry Italian breadcrumbs
  • 1/3 cup freshly grated Parmigiano-Reggiano cheese


  1. Preheat the oven 400 degrees.
  2. Lightly grease a 2-quart shallow baking dish.
  3. In a large saucepan, combine the potatoes with enough water to cover by 2 inches.
  4. Bring to a boil and cook until fork tender about 20 minutes.
  5. Drain well and use your ricer to rice the fully cooked potatoes into a bowl.
  6. Whip the riced potatoes with 4 tablespoons of the butter, the sour cream, parsley, and chopped sage.
  7. Fold in 1/2 of the Fontina and Gruyere cheese and season with salt and white pepper.
  8. Spread the potato mixture in the prepared dish in an even layer and press it in. On top of the potatoes place the rest of the shredded cheese.
  9. In a small bowl, using your fingers, blend the remaining 2 tablespoons of butter with the breadcrumbs and Parmesan until coarse crumbs form.
  10. Top the potatoes with the breadcrumb mixture. Bake for about 45 minutes, until golden and crispy on top. The assembled unbaked casserole can be refrigerated overnight.



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Chef Melissa Harrison

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