Sweet Potato Apple and Onion Gratin
Elevate your side dish game with this Sweet Potato Apple and Onion Gratin, a delectable combination of tender sweet potatoes, crisp tart apples, and caramelized onions layered in a creamy, cheesy sauce. This crowd-pleasing dish marries the natural sweetness of the ingredients with savory Gruyere and Parmesan cheese, while a hint of dried thyme adds a sophisticated herbal note. Perfect for holidays or cozy dinners, this gratin’s golden, bubbly topping will have everyone reaching for seconds. Ready in just over an hour, it’s a show-stopping accompaniment that’s as visually stunning as it is delicious.
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Recipe Information
Ingredients
- 2 large sweet potatoes
- 2 medium apples (Granny Smith or Honeycrisp preferred)
- 1 large yellow onion
- 2 tablespoons olive oil
- 2 tablespoons butter
- 2 cloves garlic
- 1 cup heavy cream
- 1 cup grated Gruyere cheese
- 1 cup grated Parmesan cheese
- 1 teaspoon dried thyme
- 1 teaspoon salt
- 0.5 teaspoon black pepper
Instructions
Preheat your oven to 375°F (190°C) and grease a 9x13-inch baking dish with butter or cooking spray.
Peel the sweet potatoes and slice them into thin rounds, about 1/8-inch thick. Core the apples (peeling is optional) and slice them into thin rounds or half-moon shapes. Peel the onion and slice into thin rounds.
Heat 1 tablespoon of olive oil and 1 tablespoon of butter in a skillet over medium heat. Add the onion slices and cook, stirring frequently, until caramelized (about 10-12 minutes). Remove from heat and set aside.
In a small saucepan, melt the remaining 1 tablespoon of butter over medium heat. Add minced garlic and sauté for 1-2 minutes until fragrant (do not let it brown). Stir in the heavy cream, dried thyme, salt, and black pepper. Heat until the cream is warm but not boiling, then remove from heat.
Layer one-third of the sweet potatoes in the bottom of the prepared baking dish, slightly overlapping the slices. Top with one-third of the apple slices, followed by half of the caramelized onions. Sprinkle one-third of the Gruyere and Parmesan cheeses over the layer.
Repeat with another layer of sweet potatoes, apples, the remaining onions, and another third of the cheese. Finish with a final layer of sweet potatoes and apples.
Pour the warm cream mixture evenly over the layers, ensuring it seeps throughout the dish. Top with the remaining Gruyere and Parmesan cheeses.
Cover the dish with foil and bake in the preheated oven for 30 minutes. Remove the foil and bake for an additional 15 minutes to allow the top to bubble and turn golden brown.
Let the gratin rest for 5-10 minutes before serving. Garnish with fresh thyme if desired and enjoy!
Nutrition Facts
Calories |
2633 | ||
|---|---|---|---|
% Daily Value* |
|||
| Total Fat | 192.1 g | 246% | |
| Saturated Fat | 102.5 g | 512% | |
| Polyunsaturated Fat | 3.4 g | ||
| Cholesterol | 486 mg | 162% | |
| Sodium | 4956 mg | 215% | |
| Total Carbohydrate | 146.8 g | 53% | |
| Dietary Fiber | 23.8 g | 85% | |
| Total Sugars | 67.3 g | ||
| Protein | 74.3 g | 149% | |
| Vitamin D | 0.3 mcg | 1% | |
| Calcium | 2203 mg | 169% | |
| Iron | 4.3 mg | 24% | |
| Potassium | 793 mg | 17% | |
*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
