Description
A comforting layered gratin featuring tender sweet potatoes and apples baked with a creamy Brie sauce, tart dried cranberries, and a golden walnut crumble. Fresh thyme brings everything together for an elegant side dish perfect for holiday dinners and family gatherings.
Ingredients
For the Sweet Potato & Apple Layers:
3 medium sweet potatoes, peeled and thinly sliced (750 g)
3 medium apples, peeled, cored, and thinly sliced (450 g)
2 tbsp unsalted butter, melted (28 g)
1 tbsp pure maple syrup (20 g)
1 tsp fresh thyme leaves (2 g)
½ tsp ground cinnamon (1.5 g)
½ tsp salt (3 g)
¼ tsp black pepper (0.5 g)
For the Creamy Brie Sauce:
6 oz Brie cheese, rind removed and chopped (170 g)
1 cup heavy cream (240 ml)
½ cup whole milk (120 ml)
1 clove garlic, minced (3 g)
¼ tsp ground nutmeg (0.5 g)
¼ tsp salt (1.5 g)
For the Walnut Crumble:
¾ cup walnuts, roughly chopped (85 g)
½ cup panko breadcrumbs (30 g)
2 tbsp all-purpose flour (16 g)
2 tbsp unsalted butter, melted (28 g)
2 tbsp dried cranberries, finely chopped (20 g)
1 tbsp fresh thyme leaves (3 g)
For the Topping:
⅓ cup dried cranberries (50 g)
1 tbsp fresh thyme leaves (3 g)
Instructions
1. Preheat the oven to 375°F (190°C). Lightly grease a 9×13-inch (23×33 cm) baking dish.
2. Arrange alternating layers of thinly sliced sweet potatoes and apples in the prepared baking dish, slightly overlapping each slice. Drizzle evenly with melted butter and maple syrup, then sprinkle with fresh thyme, cinnamon, salt, and black pepper.
3. Combine the heavy cream, whole milk, minced garlic, nutmeg, and salt in a small saucepan over medium-low heat. Warm gently without boiling. Add the chopped Brie and stir until melted into a smooth, creamy sauce.
4. Pour the warm Brie sauce evenly over the sweet potato and apple layers, allowing it to settle between the slices.
5. In a bowl, combine the chopped walnuts, panko breadcrumbs, flour, melted butter, finely chopped dried cranberries, and fresh thyme. Stir until evenly coated and crumbly.
6. Scatter the walnut crumble evenly over the gratin and sprinkle the remaining dried cranberries over the top.
7. Cover the baking dish loosely with foil and bake for 40 minutes. Remove the foil and continue baking for 20–25 minutes, or until the sweet potatoes are tender and the walnut topping is golden and crisp.
8. Let the gratin rest for 10–15 minutes before serving. Finish with fresh thyme and serve warm.
Notes
Slice the sweet potatoes and apples evenly so they cook at the same rate and create neat layers. Warm the cream and milk gently without boiling before adding the Brie for a smooth sauce. Covering the gratin during the first part of baking helps the sweet potatoes become tender before the crumble browns. Watch the final 20–25 minutes closely so the walnut topping becomes golden and crisp without over-browning. Let the gratin rest for 10–15 minutes before serving so the creamy Brie sauce can settle between the layers. Crisp apples with a balance of sweetness and tartness work well because they hold their shape during baking. Prepare the sliced ingredients, Brie sauce, and walnut crumble separately ahead of time, then assemble and bake when ready. For the best texture, add the walnut crumble just before baking. Another mild, soft cheese that melts well can be substituted for Brie, although the flavour and texture will be different. Serve warm alongside roasted chicken, turkey, pork, or another favourite main course. Finish with fresh thyme and a few extra toasted walnuts for presentation.
- Prep Time: 20 minutes
- Cook Time: 65 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: American