5 from 12 votes
Sweet Potato Au Gratin Recipe
This Sweet Potato Au Gratin features thinly sliced sweet and russet potatoes cooked gently in a warm Mornay sauce before being baked with a crispy breadcrumb topping. The result is a creamy, tender potato dish with a golden browned crust and subtle herb garnish that complements the richness. It is a comforting casserole ideal for serving as a side dish, especially when prepared ahead and reheated.
Prep Time
25 mins
Cook Time
45 mins
Servings:
12
Calories:
260 kcal
Course:
Side Dish, Appetizer, Lunch, Dinner
Cuisine:
American
Ingredients
- 1 Mornay sauce recipe
- 4 sweet potato peeled, thinly sliced
- 1 russet potato peeled and thinly sliced
- 1 cup breadcrumbs
- 2 tablespoons olive oil
- thyme fresh, minced, for garnish
Instructions
- Preheat the oven to 350°.
- Keep the mornay sauce hot over low heat in a large rondeau or pot.
- Add the sweet potatoes and russet potatoes to the pot with mornay and cook over low heat for 12 to 15 minutes just to start the cooking process of the potatoes. Gently stir the mixture every 2 to 3 minutes using a rubber spatula or spoon.
- Transfer the mixture to a 13x9 or 12x8 casserole dish and smooth it out on top by gently pressing down.
- In a small bowl, mix together the breadcrumbs and olive oil until mixed.
- Evenly sprinkle the breadcrumbs all over the sweet potato mixture until covered.
- Bake in the oven at 350° for 30 to 35 minutes or until the breadcrumbs are browned and the potatoes are tender. Do not overcook, or the sauce will break.
- Remove from the oven and let it rest for about 10 minutes. Garnish with the option of fresh chopped thyme, rosemary, or parsley.
Cup of Yum
Notes
- This dish can be prepared up to one day in advance and reheated before serving.
- Store leftovers covered in the refrigerator for up to four days, or freeze for up to two months after wrapping well.
- To reheat, bake covered in foil at 375°F until hot, or microwave portions until warmed through.
- Use any type of sweet potato or yam as needed for the recipe.
- Do not overbake to avoid the sauce breaking and becoming watery, which affects texture and appearance.
- Add fresh herbs like thyme or rosemary to the Mornay sauce if desired for enhanced flavor.
Nutrition Information
Calories
260kcal
(13%)
Carbohydrates
29g
(10%)
Protein
9g
(18%)
Fat
12g
(18%)
Saturated Fat
6g
(30%)
Polyunsaturated Fat
0.4g
(2%)
Monounsaturated Fat
2g
(10%)
Cholesterol
28mg
(9%)
Sodium
247mg
(10%)
Potassium
467mg
(10%)
Fiber
3g
(12%)
Sugar
8g
(16%)
Vitamin A
11004IU
(220%)
Vitamin C
3mg
(3%)
Calcium
278mg
(28%)
Iron
1mg
(6%)
Nutrition Facts
Serving: 12 Serving
Amount Per Serving
Calories 260
% Daily Value*
| Calories | 260kcal | 13% |
| Carbohydrates | 29g | 10% |
| Protein | 9g | 18% |
| Fat | 12g | 18% |
| Saturated Fat | 6g | 30% |
| Polyunsaturated Fat | 0.4g | 2% |
| Monounsaturated Fat | 2g | 10% |
| Cholesterol | 28mg | 9% |
| Sodium | 247mg | 10% |
| Potassium | 467mg | 10% |
| Fiber | 3g | 12% |
| Sugar | 8g | 16% |
| Vitamin A | 11004IU | 220% |
| Vitamin C | 3mg | 3% |
| Calcium | 278mg | 28% |
| Iron | 1mg | 6% |
* Percent Daily Values are based on a 2,000 calorie diet.