Go Back
–+ servings
Sweet Potato Pasta Gratin

Sweet Potato Pasta Gratin

The Crispy Chef
This creamy, cheesy sweet potato pasta gratin is the ultimate fall comfort food — layers of roasted sweet potatoes, pasta, and bubbling Gruyère cheese sauce baked to golden perfection. It's cozy, elegant, and totally irresistible.
Print Recipe Pin Recipe
Prep Time 30 minutes
Cook Time 40 minutes
Total Time 1 hour 10 minutes
Course Main, Side
Cuisine American
Servings 8 servings
Calories 485 kcal

Equipment

  • Large rimmed baking sheet
  • Large pot (for pasta)
  • Large skillet
  • Medium saucepan
  • 9x13-inch baking dish
  • Whisk
  • Sharp Knife
  • Cheese grater

Ingredients
  

  • 2 lbs sweet potatoes (medium-sized, peeled and cubed)
  • 12 oz penne or rigatoni pasta
  • 3 tbsp olive oil
  • 1 large onion, thinly sliced
  • 4 cloves garlic, minced
  • 2 tbsp fresh sage leaves (or 1 tsp dried)
  • to taste salt and black pepper
  • 1/4 tsp ground nutmeg
  • pinch red pepper flakes (optional)
  • 4 tbsp butter
  • 4 tbsp all-purpose flour
  • 3 cups whole milk (warmed)
  • 1 cup heavy cream
  • 2 cups Gruyère cheese, grated
  • 1 cup sharp white cheddar, grated
  • 1/2 cup Parmesan cheese, grated
  • 1 tsp Dijon mustard
  • 1/2 tsp salt
  • 1/4 tsp white pepper
  • 1 cup panko breadcrumbs
  • 1/2 cup grated Parmesan (for topping)
  • 3 tbsp butter, melted
  • 2 tbsp fresh thyme leaves
  • to taste extra Gruyère for topping

Instructions
 

  • Preheat oven to 425°F (220°C) and line a baking sheet with parchment paper.
  • Peel and cube sweet potatoes into ¾-inch pieces.
  • Toss cubes with 2 tbsp olive oil, salt, and pepper. Roast 25–30 minutes until caramelized and fork-tender.
  • Cook pasta in salted water until just shy of al dente. Drain and set aside.
  • In a skillet, sauté onions in remaining olive oil until caramelized, 8–10 minutes.
  • Add garlic, sage, nutmeg, and red pepper flakes. Cook 1–2 minutes until fragrant.
  • In a saucepan, melt butter and whisk in flour. Cook 2 minutes to form roux.
  • Gradually add milk and cream, whisking constantly. Add Dijon, salt, and white pepper. Simmer until thickened.
  • Remove from heat and stir in Gruyère, cheddar, and Parmesan until melted.
  • Lower oven to 375°F (190°C). Butter baking dish.
  • Combine pasta, sweet potatoes, and onion mix in the dish. Pour in cheese sauce and fold gently.
  • Mix breadcrumbs, Parmesan, melted butter, and thyme. Sprinkle on top. Add extra Gruyère if desired.
  • Bake for 35–40 minutes until bubbly and golden brown.
  • Let rest for 10 minutes before serving.

Notes

Make it ahead by assembling without the topping and refrigerate up to 1 day. Swap sweet potatoes for butternut squash, or add sausage for a heartier meal. Gluten-free and herb variations included!

Nutrition

Calories: 485kcalCarbohydrates: 52gProtein: 18gFat: 22gSaturated Fat: 13gPolyunsaturated Fat: 2gMonounsaturated Fat: 6gTrans Fat: 0.5gCholesterol: 75mgSodium: 580mgPotassium: 750mgFiber: 4gSugar: 7gVitamin A: 9200IUVitamin C: 4mgCalcium: 250mgIron: 2.1mg
Keyword cheesy baked pasta, fall gratin, sweet potato pasta, vegetarian casserole
Tried this recipe?Mention @Thecrispycheff or tag #Thecrispychef!