Save This Alfredo Sweet Potato Lasagna is pure comfort layered in every slice—it is my go-to for cozy, chilly nights when I crave richness without the heaviness of meat. Sweet potatoes replace traditional pasta for sweetness and texture while creamy Alfredo sauce and mozzarella turn this vegetarian main dish into an irresistible family favorite.
I made this for a fall dinner and it quickly became a staple for celebrations and weeknight comfort alike. It warms the kitchen and makes the house smell amazing.
Ingredients
- Sweet potatoes: Bring natural sweetness and tender body. Slice them very thin for best results. Choose firm potatoes without dark spots for easy slicing
- Fresh baby spinach: Cooks down to a gentle earthy flavor and adds color. Pick bright green leaves without wilting
- Onion and garlic: Provide depth and classic warmth. Use a small yellow onion for sweetness and fresh garlic cloves for bold aroma
- Olive oil: For sautéing and layering flavor. A good quality olive oil adds fruity notes
- Butter: Gives the Alfredo sauce richness and classic Italian flavor. Go for unsalted so you control the seasoning
- All-purpose flour: For thickening the Alfredo sauce. Sifted flour makes the sauce smoother
- Whole milk and heavy cream: Create the silky creamy base of the sauce. Fresh dairy makes a difference here
- Parmesan cheese: Offers sharp salty backbone to the sauce. Grate it yourself for best flavor
- Ground nutmeg: Gives a special warmth to Alfredo sauce. Buy whole nutmeg and grate for freshness if you can
- Salt and black pepper: For seasoning. Kosher salt for even flavor, freshly cracked pepper for brightness
- Ricotta cheese: Dots the layers for creaminess. Look for ricotta with fewest ingredients on the label—fresh is best
- Mozzarella cheese: Melts into gooey cheesy pulls. Shred your own for a better melt and flavor
- Fresh basil: Brightens it at the end. Use whole leaves or chop for garnish. Only add before serving for the brightest color
Instructions
- Preheat and Prep the Dish:
- Set oven to 375 degrees Fahrenheit and grease a 9 by 13 inch baking dish. Drizzle in olive oil for flavor and prevent sticking
- Sauté the Aromatics:
- In a large skillet over medium heat warm olive oil until shimmering. Add finely chopped onion and cook gently until translucent about three minutes. Stir in minced garlic and cook for a minute just until fragrant. Toss in the fresh spinach and cook for two minutes until just wilted then remove from heat. This builds the first layer of savory flavor beneath the creamy sauce
- Make the Alfredo Sauce:
- In a medium saucepan melt unsalted butter on medium heat. Sprinkle in flour and whisk for one minute so it forms a paste and cooks out the flour taste. Whisk in whole milk and heavy cream slowly until smooth and let it thicken stirring constantly. This takes about four to five minutes. When it coats a spoon stir in grated Parmesan nutmeg salt and pepper. Taste and adjust. The sauce should be thick but pourable
- Begin Layering:
- Spread a thin layer of Alfredo sauce over the bottom of your greased baking dish. This prevents sticking and ensures the first bite is never dry
- Layer Sweet Potatoes:
- Arrange sweet potato slices in a single overlapping layer covering the entire surface. This gives the structure and sweetness
- Build Cheese and Greens Layer:
- Top the sweet potatoes with half the sautéed spinach mixture. Then dot half the ricotta all over. Spoon Alfredo sauce over this and sprinkle mozzarella for melty goodness
- Repeat Layers:
- Add another layer of sweet potato slices followed by the rest of the spinach ricotta more Alfredo sauce and another mozzarella layer. Again slightly overlap the potatoes
- Final Layer and Cheese:
- Finish with one last layer of sweet potatoes the rest of the Alfredo sauce and a generous final sprinkle of mozzarella cheese. This ensures each bite is ultra creamy and cheesy on top
- Bake Covered Then Uncovered:
- Cover the dish tightly with foil. Bake for thirty minutes so everything steams and cooks through. Remove the foil and bake uncovered for fifteen to twenty more minutes to brown the cheese and finish cooking. Let it go until sweet potatoes yield easily to a knife and the top is golden and bubbling
- Rest and Serve:
- Allow lasagna to rest for about ten minutes out of the oven so the layers set. Slice carefully and shower the top with freshly chopped basil for a fragrant finish
Save One of the best memories I have with this dish is serving it at a friendsgiving—everyone piled their plates high and it disappeared so quickly. My favorite part is the Alfredo sauce which I make extra creamy and peppery for that restaurant feel at home
Storage Tips
Let the lasagna cool completely before storing. Place leftovers in an airtight container and refrigerate for up to four days. For reheating cover with foil and warm in a low oven or microwave until heated through. The flavor actually develops more the next day making it even better for lunch
Ingredient Substitutions
Swap in kale for spinach for a heartier flavor or use any leafy green on hand. Dairy free versions can be made using oat milk plant based butter and vegan cheese. Use gluten free flour for a wheat free Alfredo sauce. If sweet potatoes are not available try thinly sliced butternut squash which offers a slightly sweeter flavor
Serving Suggestions
Brighten your table with a crisp green salad tossed in lemon vinaigrette or serve with garlicky roasted broccoli. A glass of chilled Pinot Grigio or sparkling water with lemon complements the richness. For extra zest offer red pepper flakes at the table
Cultural or Historical Context
This recipe draws on Italian American lasagna traditions but swaps pasta for sweet potatoes—an old world technique used in rustic cooking to stretch ingredients. The Alfredo sauce brings a nod to classic fettuccine but in a baked casserole form. It is Italian inspired but with a cozy American twist
Seasonal Adaptations
In autumn replace spinach with roasted Swiss chard or kale. In summer use thinly sliced zucchini in place of some sweet potato. Springtime is perfect for adding roasted asparagus or peas into the filling
Success Stories
Many home cooks tell me this was their first successful vegetarian main dish. Some even convert meat lovers with the creamy cheesy layers. When I first made it for new neighbors they asked for the recipe before dessert was served
Freezer Meal Conversion
You can assemble this lasagna a day or two in advance or freeze the whole unbaked dish tightly covered. Thaw overnight in the fridge then bake as directed or add more time from frozen. Individual slices freeze well too making easy lunches
Save This cozy lasagna is sure to be a new favorite at your table. Each bite is creamy, cheesy, and full of sweet potato goodness