Sweet Potato Gratin with Leeks and Onions

This dish is the perfect choice when you want a sweet and savory, delicious combination.

Serves: 10Hands-on: 15 minutesTotal: 1 hour 15 minutesDifficulty: Medium

Serves: 10


  • 2 leeks, white part only, rinsed and chopped
  • 2 large sweet onions, peeled and sliced
  • 2 cloves garlic, peeled and minced
  • 2 stalks celery with tops, finely chopped
  • 4 Tbsp. extra-virgin olive oil
  • 4 large sweet potatoes, peeled and sliced thinly
  • 1 tsp. dried thyme
  • 1⁄2 tsp. salt
  • 1⁄2 tsp. ground black pepper
  • 2 cups whole milk
  • 1 1⁄2 cups cornbread crumbs
  • 2 Tbsp. butter, cut into small pieces


  • Preheat the oven to 325°F. Prepare large gratin pan or baking dish with nonstick spray.
  • In a large pan over medium heat, sauté the leeks, onions, garlic, and celery in olive oil or butter.
  • Layer the sweet potato slices in the gratin pan with the vegetables. Sprinkle with thyme, salt, and pepper as you go along.
  • Finish with a layer of potatoes. Add the milk until it meets the top layer of potatoes, then add the cornbread crumbs. Dot with butter.
  • Bake until the potatoes are soft, about 1 hour.