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Autumn Au Gratin Potatoes

Autumnal Au Gratin Potatoes

This recipe takes the traditional au gratin potatoes and puts a fall flavor twist on it. Sweet potatoes, chicken sausage, kale, mushrooms and sage combine in this delicious, cool weather casserole.
Prep Time 20 mins
Cook Time 1 min
Total Time 21 mins
Servings 8 people


  • 1 tablespoon extra-virgin olive oil
  • 1 pound fully-cooked chicken sausage
  • 4 tablespoons salted butter divided
  • 8 oz cremini or white button mushrooms sliced
  • 1/2 teaspoon Salt
  • 1 teaspoon Black Pepper divided
  • fresh kale wash and cut into bite-sized pieces to make 3 cups
  • 3 medium sweet potatoes
  • 3 medium white russet potatoes
  • 1/2 cup onion
  • 1 tablespoon flour flour
  • 1 tablespoon dry sage
  • 1/2 teaspoon crushed red pepper
  • 1/4 teaspoon nutmeg
  • 2 cups 2% or whole milk room temperature
  • 1 cup shredded cheddar cheese divided, room temperature
  • 1 cup shredded swiss cheese divided, room temperature
  • 1/2 cup Parmesan cheese
  • 1/4 cup dry bread crumbs
  • 1/4 teaspoon paprika


  • Preheat oven to 325 degrees.
  • Heat olive oil in a skillet over medium heat; add sausage pieces, lightly browning. Remove from pan and set aside, reserving one tablespoon of drippings in the pan.
  • Add one tablespoon of butter and the sliced mushrooms to the skillet. Cook, stirring occasionally, until mushrooms are brown (about 5-7 minutes). Sprinkle mushrooms with salt and 1/2 teaspoon of the black pepper. Remove mushrooms from the pan and set aside. Add kale to the hot pan and cook, 2-3 minutes, until kale wilts. Remove kale and set aside.
  • Peel and thinly slice potatoes.
  • Place 1/3 of potatoes in bottom of a 9”x13” pan. Cover with 1/2 of the chicken sausage, 1/2 of the mushrooms and 1/2 of the kale. Repeat layering, ending with a final layer of potatoes.
  • Melt remaining butter in the skillet over very low heat. Stir in onions and sauté until tender, 3-4 minutes. Whisk in flour, 1/2 teaspoon black pepper, sage, crushed red pepper and nutmeg, stirring constantly until bubbly (1-2 minutes). Slowly stir in milk (1/2 cup at a time) and bring back to a very low boil, whisking constantly. Add 1 1/2 cups of the shredded cheese (1/2 cup at a time) whisking after each addition until melted. Stir in Parmesan cheese. Pour sauce over potato/meat/vegetable layers. Use a fork to gently distribute the sauce throughout the potatoes.
  • Bake, uncovered, for 1 hour and 20 minutes.
  • Combine bread crumbs, remaining cheese and paprika. Sprinkle on top of casserole and return to oven for 20 minutes, or until top is brown and bubbly.
Keyword casserole, kale, potatoes, sausage, sweet potatoes