Easy Sweet Potato Gratin Recipe

  • 1/4 cup canola oil
  • 2 large onions, thinly sliced
  • 4 pounds sweet potatoes, peeled and very thinly sliced
  • 2 cups heavy whipping cream
  • 1 cup maple syrup
  • salt to taste
  1. Preheat oven to 375 degrees F (190 degrees C).
  2. Heat oil in a skillet over medium-low heat; cook and stir onions until tender and golden, about 30 minutes.
  3. Place sweet potatoes in a large bowl.
  4. Heat cream and maple syrup together in a saucepan over high heat; cook and stir until almost boiling, about 5 minutes. Pour 2/3 the cream mixture over sweet potatoes; toss to evenly coat.
  5. Layer potatoes in a 9×13-inch casserole dish, seasoning with salt every 5 to 6 layers. Pour remaining cream mixture over potatoes until potatoes are 3/4 covered. Cover dish with aluminum foil.
  6. Bake in the preheated oven for 30 minutes. Remove aluminum foil and gently stir potatoes; top with caramelized onions. Bake until potatoes are tender, about 20 more minutes. Allow to cool for about 30 minutes before serving.