A savory sweet potato casserole! Imagine that, no marshmallow topping, no pecans, no brown sugar. Instead, sweet potatoes get the savory treatment with sage, shallots, Parmesan and a little bit of Dijon. The creamy mashed sweet potato filling is to die for and the crunchy crouton-sage topping makes it heavenly.
Table of Contents
Why We Love this Recipe
First and foremost, I love this recipe is because it’s savory, not cloyingly sweet like so many sweet potato casseroles. I find savory ingredients like cheese, shallots and Dijon do a better job of highlighting the flavor of sweet potatoes, not mask it.
I also love how easy this sweet potato casserole is to make. The croutons and fried sage can be cooked on the stovetop while the potatoes roast in the oven. Once the potatoes are tender they’re tossed in a blender and mixed with the rest of the filling. This dish is stunning and impressive while requiring very little work.
Ingredients in this Savory Sweet Potato Casserole
Kosher salt, black pepper and olive oil are assumed ingredients.
- Sweet potatoes, are the base of this recipe! You’ll need 2 to 3 medium sweet potatoes.
- Fresh sage is an important ingredient in this recipe. There’s really no substitute because the leaves get fried in oil. If you want to skip the frying of the herb, you can use fresh thyme or minced rosemary instead.
- Sourdough bread, you can also use a hearty whole-grain bread if you prefer.
- Olive oil or avocado oil mayonnaise, I really like Sir Kensington’s mayo.
- Grated Parmesan, you can find grated Parmesan in the specialty cheese section.
- Egg is important for binding and giving the casserole a bit of structure.
- Dijon mustard adds savoriness to the casserole.
- Nutmeg compliments the flavors of sweet potato, Parmesan and sage. It also adds a slight warmth to the dish.
- Lemon zest gets sprinkled over top and adds a nice brightness to balance out all of the savory flavors.
How to Make this Sweet Potato Casserole
- Roast the sweet potatoes in the oven until soft.
- Meanwhile, fry the sage leaves in olive oil on the stove top.
- Toast the bread pieces on the stove top as well; set croutons aside.
- Cook the shallot in oil until softened; transfer to a blender.
- Add the cooked sweet potatoes, mayo, Parmesan, egg, Dijon, and nutmeg to blender with cooked shallot and blend until smooth.
- Transfer the sweet potato mixture to a baking dish and top with fried sage and croutons. Bake until topping is crispy and golden brown and filling is hot.
- Finish with fresh lemon zest and serve.
FAQs and Test Kitchen Tips
I haven’t tested this, but you should be able to substitute the mayo with an extra egg and ¾ cup half-and-half, heavy cream, or melted butter.
You can prep the filling and the toppings up to 3 days ahead of time. Store the filling in an airtight container in the refrigerator. Store the croutons and sage in an airtight container on the stove top.
Assemble the casserole and bake when ready to serve.
Savory Sweet Potato Casserole Recipe
- 2 ½ pounds medium sweet potatoes, halved lengthwise
- ¼ cup sage leaves
- 3 tablespoons extra-virgin olive oil, divided
- 1 ½ cups sourdough bread, broken into craggy pieces
- Kosher salt and cracked black pepper
- 1 large shallot, chopped
- ½ cup olive oil or avocado oil mayonnaise*
- ½ cup grated Parmesan (2 ounces)
- 1 large egg
- 1 tablespoon Dijon mustard
- ¼ teaspoon freshly grated nutmeg
- ½ teaspoon finely grated lemon zest
- Heat oven to 350°F (176ºC) with racks set in upper-third and lower-third of oven. Line a baking sheet with foil. Place potatoes, cut side down on prepared sheet and prick skins with fork.
- Roast potatoes until very tender 1–1½ hours. Cool completely on sheets. Increase oven to 400°F (204ºC).
- Heat 2 tablespoons oil over medium-high in a sauté pan until shimmering. Add sage and cook until starting to brown and crisp, 2–3 minutes.
- Transfer sage to a paper-towel lined plate. Add bread to remaining oil in pan and cook, stirring frequently, until crispy and golden brown, about 4 minutes; season with salt and pepper.
- Heat remaining tablespoon oil in sauté pan over medium, add shallot and cook, stirring occasionally, until starting to brown, about 5 minutes.
- Scoop flesh from potatoes and transfer to a blender; discard skins. Add cooked shallots, mayonnaise, Parmesan, egg, Dijon, nutmeg and ¼ teaspoon each salt and pepper to blender with potatoes; blend until smooth.
- Transfer potato mixture to a shallow 1-quart baking dish, smooth top with a spatula then create some divots.
- Sprinkle sage and breadcrumbs evenly over sweet potatoes. Bake casserole on upper rack until top is golden and crisp, 20-25 minutes. Sprinkle lemon zest over top and cool 10 minutes.