This Sweet Potato Cranberry Gratin is the kind of comfort dish that looks elegant but comes together simply — perfect for holiday tables or a cozy weeknight side. I’ve made it several times, swapping cheeses and toppings, and it always delivers a sweet-tart lift with a golden, bubbling top. If you like layered, cheesy casseroles, try this after enjoying a similar twist on a sweet-potato gratin like this sweet potato kale gratin recipe for more inspiration.
Why Make This Recipe
- Bright, balanced flavor: sweet roasted sweet potatoes and tart cranberries create a pleasing contrast in every bite.
- Crowd-pleaser: it feeds 6–8 and holds well on a buffet or holiday table.
- Nutrient-rich: sweet potatoes add vitamin A and fiber while cranberries add antioxidants.
- Make-ahead friendly: you can assemble it a day ahead and bake when guests arrive.
- Personal note: I love this recipe because the cranberry layer keeps the gratin from feeling too heavy — it brightens each cheesy spoonful. Also great if you enjoyed cozy soups like this sweet potato curry soup on chilly nights.
Recipe Overview
- Prep time: 20–30 minutes (plus optional par-cooking 10 minutes)
- Cook time: 45–55 minutes
- Total time: 1 hour 5 minutes (with optional par-cook)
- Servings: 6–8 as a side
- Difficulty: Easy–Medium (requires thin slicing; a mandoline helps)
- Method: Layered gratin baked in a 9×13-inch (or similar) ovenproof dish at 375°F (190°C) until tender and golden.
My Experience Making This Recipe
I tested this gratin multiple times, adjusting liquid and bake time to avoid sogginess while keeping the layers creamy. The biggest discovery was that a short par-cook of sweet potato slices (3–5 minutes in simmering water) speeds baking and guarantees tenderness without over-browning the edges.
How to Make Cozy Up with Sweet Potato Cranberry Gratin Perfection
Start by slicing 2 pounds of sweet potatoes 1/8-inch thick — a mandoline makes this fast and uniform. Sauté 1 small onion in 2 tablespoons butter until soft, then stir in 1 cup fresh or frozen cranberries and 2 tablespoons maple syrup briefly to macerate. Layer potatoes in a buttered 9×13-inch dish, seasoning each layer with salt, pepper, and a pinch of nutmeg; scatter cranberry-onion mix between layers. Pour 1 cup warm heavy cream (or half-and-half) mixed with 1 beaten egg over the top, sprinkle 1 cup grated Gruyère or sharp cheddar and 1/2 cup chopped pecans or panko for crunch. Cover with foil and bake at 375°F (190°C) for 30 minutes, remove foil and bake another 15–25 minutes until bubbling and golden. Let rest 10 minutes before serving to let the gratin set.
Expert Tips for Success
- Slice evenly: use a mandoline or sharp chef’s knife to get 1/8-inch slices so all pieces cook at the same rate. Also see this comforting crockpot turkey sweet potato stew for different sweet potato prep ideas.
- Par-cook for tenderness: if your oven runs cool or potatoes are thick, simmer slices 3–5 minutes to jump-start tenderness. This prevents over-browning while ensuring cooked-through potatoes.
- Control liquid: whisk cream with one egg to thicken the custard; avoid adding extra liquid unless the potatoes are very dry.
- Toast nuts/panko separately: pan-toast chopped pecans or panko in 1 tablespoon butter until golden and sprinkle in the last 10 minutes of baking for crisp topping. Learn more about warming spices in dishes like this turmeric chicken soup for cross-technique inspiration.
- Equipment: a 9×13-inch ovenproof dish and a mandoline are the two pieces that make this repeatable and foolproof.
How to Serve Cozy Up with Sweet Potato Cranberry Gratin Perfection
- Holiday centerpiece: serve alongside roast turkey or glazed ham; the tart cranberries pair incredibly well with rich meats. You can reference this warm caramel apple dump cake for dessert pairing ideas at cozy gatherings.
- Weeknight side: pair with roasted chicken and a simple green salad for an easy family meal.
- Presentation: scoop into a shallow serving dish and sprinkle fresh thyme leaves and a few whole cranberries for color.
- Occasion tips: double the recipe for a potluck and bake in two pans, or use a smaller dish for a thicker, creamier gratin.
Storage and Reheating Guide
- Refrigeration: cool completely, cover tightly with foil or an airtight container, and refrigerate up to 4 days.
- Freezing: portion into freezer-safe containers and freeze up to 3 months. Thaw in the refrigerator overnight before reheating.
- Reheating: reheat covered at 350°F (175°C) for 15–25 minutes until warmed through. For a crisp top, uncover for the last 5–8 minutes or broil briefly on low. Microwaving works for single portions but softens the topping.
Recipe Variations
- Gluten-free: replace panko with gluten-free panko or extra toasted chopped pecans for crunch.
- Dairy-free/vegan: use full-fat canned coconut milk or cashew cream and olive oil instead of butter; swap cheese for dairy-free shredded cheese.
- Savory twist: add 1 cup cooked crumbled sausage or torn roasted turkey between layers for a heartier main.
- Herb and spice changes: swap thyme for rosemary and add 1/4 teaspoon smoked paprika for a smoky note.
Nutritional Highlights
- Key benefits: high in vitamin A (from sweet potatoes) and fiber; cranberries add antioxidants and vitamin C.
- Allergens: contains dairy (cream, cheese) and may contain nuts (pecans) or gluten if using standard panko; adjust per variations above.
- Portion guidance: plan about 3/4–1 cup per person as a side; larger if serving as a main with protein.
Troubleshooting Common Issues
- Potatoes still firm after baking: slices were too thick; next time slice thinner (1/8 inch) or par-cook slices 3–5 minutes.
- Top burns before center is cooked: cover with foil for the first part of baking, remove for the final 15–20 minutes to brown.
- Gratin too watery: reduce cream by 1/4 cup, drain any excess from cranberries if very juicy, and use one egg in the custard to help set the layers.
Frequently Asked Questions
Q: Can I use frozen sweet potato slices?
A: Yes, but thaw and pat very dry first. Frozen slices release water as they defrost; drying prevents a watery gratin and helps the custard set properly.
Q: Are fresh cranberries necessary or can I use dried/cranberry sauce?
A: Fresh or frozen cranberries are best for bright tartness. Dried cranberries are sweeter and chewier; if using cranberry sauce, reduce added sweetener and spread thinner to avoid excess moisture.
Q: Can I assemble this the night before?
A: Absolutely. Assemble, cover tightly, and refrigerate. Add 10–15 minutes to the bake time if baking from cold. Bring to room temperature for 20 minutes before baking for more even cooking.
Q: How do I get a golden, crunchy top without overcooking the potatoes?
A: Start covered at 375°F (190°C) for 30–35 minutes, then remove the foil and broil or bake uncovered for 10–15 minutes. Toasted nuts or panko added in the final minutes stay crisp without burning.
Conclusion
If you want another savory gratin idea with greens and sweet potato, the classic approach from Smitten Kitchen is a lovely reference for technique and flavor balance: swiss chard and sweet potato gratin – smitten kitchen.
Sweet Potato Cranberry Gratin
- Total Time: 75 minutes
- Yield: 6–8 servings
- Diet: Vegetarian
Description
A comforting yet elegant layered gratin featuring sweet roasted sweet potatoes and tart cranberries, perfect for holiday tables or cozy dinners.
Ingredients
- 2 pounds sweet potatoes, sliced 1/8-inch thick
- 1 small onion, sautéed
- 2 tablespoons butter
- 1 cup fresh or frozen cranberries
- 2 tablespoons maple syrup
- Salt and pepper to taste
- Pinch of nutmeg
- 1 cup warm heavy cream (or half-and-half)
- 1 beaten egg
- 1 cup grated Gruyère or sharp cheddar cheese
- 1/2 cup chopped pecans or panko for topping
Instructions
- Sauté the onion in butter until soft, then mix in cranberries and maple syrup.
- Layer sweet potatoes in a greased 9×13-inch dish, seasoning each layer with salt, pepper, and nutmeg, adding the cranberry-onion mixture between layers.
- In a bowl, combine warm cream and beaten egg; pour over the layered vegetables.
- Top with grated cheese and nuts or panko.
- Cover with foil and bake at 375°F (190°C) for 30 minutes.
- Remove foil and bake an additional 15-25 minutes until golden and bubbling.
- Let rest for 10 minutes before serving.
Notes
Can be assembled a day in advance; cover tightly and refrigerate before baking. For best results, use a mandoline for even slicing.
- Prep Time: 30 minutes
- Cook Time: 45 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: American