Sweet Potato Pie with Walnut Crust

Better than pumpkin—really

What’s for dessert this Thanksgiving? Pie, of course—why even bother to ask? And pumpkin will be the pie of choice for most households throughout the US.

But how about an alternative that’s even tastier? That would be Sweet Potato Pie, a favorite in the American South. Sweet potatoes have deeper, richer flavor than pumpkin. And our gluten-free walnut crust is both tastier and easier to make than the traditional pastry shell.

So welcome to the best Thanksgiving dessert. Ever.

Recipe: Sweet Potato Pie with Walnut Crust

Pumpkins and sweet potatoes hail from two different botanical families (Cucurbitaceae for pumpkin, Convolvulaceae—morning glory—for sweet potatoes). But when made into pie, they have remarkably similar flavor profiles. Indeed, they’re often spiced almost identically. Sweet Potato Pie has loads more oomph, though.

There are two types of sweet potatoes commonly found in the US. One has reddish brown skin and deep orange flesh, while the other has golden-toned skin and yellowish flesh. The first kind (which tend to be sweeter) are sometimes called “yams”—though this is a misnomer. Real yams are an entirely different veggie; they’re not even related to sweet potatoes (and they’re not easy to find in US markets).

Any sweet potato you’re likely to see in your local market should work in this recipe—which is quite straightforward, BTW. There are 3 major steps, none of them difficult. First, you need to make the crust and blind bake it (that is, bake it without a filling). Second, you need to cook the sweet potatoes and purée them. (We boil the sweet potatoes, but you could use another cooking method if you prefer; more on this in the Notes). Third, you need to mix the pie filling and bake the pie.

Mrs. Kitchen Riffs is the baker in our household, and this recipe is hers. The crust is the same one we used in our recipe for Lemon Cheesecake with Walnut Crust. If you prefer, you can substitute a pastry crust (your own or store bought). If you use a pastry crust, you can blind bake it or not—your choice. The filling for this pie was adapted from a recipe in James Beard’s American Cookery.

Prep time for making the crust is about 10 minutes, and baking time is 15 to 20 minutes. Prep time for cooking the sweet potatoes is 5 minutes, with cooking time of about half an hour. Prep time for making the pie filling is 10 or 15 minutes, with final baking time of 40 minutes or so.

Ingredients

For the crust (makes one 9-inch crust):

• ~2½ cups walnuts (pieces, not whole walnuts; about 10 ounces)
• ¾ cup granulated sugar
• 6 tablespoons butter, melted

For the filling:

• ~2 cups cooked sweet potatoes (about 2 medium-sized sweet potatoes; see Procedure for cooking method)
• 2 teaspoons Kosher salt for seasoning the cooking water (see Notes)
• 1 cup brown sugar, packed (or to taste; see Notes)
• 3 large eggs (preferably pasteurized; see Notes)
• 1 cup heavy whipping cream
• 1 teaspoon ground cinnamon (or to taste; see Notes)
• ½ teaspoon ground ginger (or to taste; see Notes)
• ¼ teaspoon additional Kosher salt
• ¼ teaspoon ground cloves (optional, but recommended)
• ¼ teaspoon ground nutmeg (optional, but recommended)

Procedure

For the crust:

1. Preheat oven to 350 degrees F. Butter a 9-inch Pyrex pie plate (if using a metal dish, preheat oven to 375 degrees F).
2. In a food processor, grind the walnuts with the granulated sugar until fine. Meanwhile, melt the butter in the microwave (preferably in a container with a lid; about 1 minute.) Add the butter to the walnut mixture and pulse until well mixed (it will look like wet sand).
3. Press the walnut mixture evenly around the bottom and sides of the pie plate. Bake for about 15 minutes, or until the crust is starting to brown around the edges. (While the crust is baking, you can start cooking the sweet potatoes for the filling; see below).
4. Remove the crust from the oven and allow it to cool while preparing the sweet potato filling.

For the filling:

1. Scrub the sweet potatoes and cut off their tips, but don’t peel them. Place the sweet potatoes in a cooking pot, cover with water, and add 2 teaspoons Kosher salt to season. Bring the water to a boil on the stovetop. Once the water is boiling, reduce to a simmer and cook until a paring knife or fork can be inserted easily into the center of each sweet potato. Depending on the size of the sweet potatoes, this can take about 20 to 30 minutes. When the sweet potatoes are done, drain them and place them on paper towels to cool. (See Notes for alternate methods of cooking sweet potatoes).
2. Once the sweet potatoes are cool enough to handle, preheat the oven to 350 degrees F (if you turned it off after baking the crust; preheat to 375 degrees F if using a metal baking dish).
3. Peel the sweet potatoes and cut them into chunks. Purée them with a food ricer or a food mill. Alternatively, place the cooked sweet potatoes in a medium-sized bowl and mash them with a potato masher or a heavy spoon. It’s OK if a few chunks remain.
4. Using a stand mixer (or in a large bowl, using a hand mixer), beat the puréed sweet potatoes until smooth. Add the brown sugar and beat well. Then add the eggs and mix until well incorporated. Add the whipping cream and beat until combined. Add the cinnamon, ginger, and ¼ teaspoon Kosher salt. Add the cloves and nutmeg, if using. Mix until well combined. Taste and adjust spices if necessary.
5. Pour the sweet potato mixture into the cooled walnut crust, smoothing the top. Bake for approximately 40 minutes. At the 40-minute mark, test the pie with an instant-read thermometer. If the pie filling has reached a temperature of about 170 degrees F, it’s done (see Notes). If the pie filling is not yet close to this temperature, keep baking—but check every five minutes or so to make sure you don’t overbake.
6. Once the pie is done, remove it from the oven and place it on a wire rack to cool. After it has cooled for an hour or so, wrap it in plastic shrink wrap and place it in the refrigerator for at least 4 hours (up to 24 hours) to chill and set completely (see Notes).
7. Serve the pie by itself, or garnish with ice cream or whipped cream (we particularly like to use rum-flavored whipped cream; see Notes).

Notes

• Most recipes for sweet potato pie use pastry shell crusts. We prefer a ground-walnut crust—which is tastier, as well as gluten free.
• Clear Pyrex (glass) pie plates tend to hold heat more efficiently than metal ones, so it’s a good idea to keep the oven temperature about 25 degrees cooler when baking a pie in clear glass.
• Why use a lidded container when melting the butter? Because butter can explode in the microwave, creating a mess if not contained. So not fun.
• We like to use Kosher salt in most recipes. But if you don’t have that on hand, you can use plain table salt (though I’d reduce the amount by about half since table salt is finer and more “condensed” than Kosher).
• Would you prefer to use a different method for cooking the sweet potatoes? The most flavorful way is probably to roast them. You can use our recipe for Roast Sweet Potatoes, but leave out the seasonings—and coat the sweet potatoes with melted butter instead of olive oil.
• Alternatively, you can microwave the sweet potatoes. Just peel them, cut them into chunks, and microwave them in a microwave-safe covered dish until they’re soft.
• Or you can peel the raw sweet potatoes, chunk them, and boil them.
• You can even bake the sweet potatoes, then scoop out the pulp when they’re done.
• Feel free to reduce or increase the amount of brown sugar used in the filling (we don't like our dessert pies to be extremely sweet, but you may prefer otherwise). 
• Eggs carry a slight (but real) risk of salmonella. So we suggest using pasteurized eggs when making any type of filling that you might taste raw. Although it’s unlikely the eggs you buy will be infected, why take the risk? Especially since you’ll want to taste this pie filling to test the spice level. 
• You can identify pasteurized eggs because they usually have a red “P” stamped on them.
• We like to use full-fat whipping cream in this pie filling. So it’s not a diet dessert! If the fat content is a concern, you can substitute milk for some or all of the cream (though the flavor won’t be as rich).
• The quantity and combination of spices can be varied to taste in this recipe—so don’t be afraid to experiment. You might find that you like more or less of a particular spice.
• We’ve listed cloves and nutmeg as optional because some cooks find their flavor overwhelming. We think they add a nice touch—and sweet potatoes really are robust enough to stand up to them. But your call.
• James Beard’s original recipe suggested adding a dash of molasses to the filling. We don’t usually do that, but it sounds tasty. (Brown sugar contains some molasses in any case.)
• His original recipe also noted that some cooks like to add grated orange rind to the filling. Again, not something we usually opt for, but you might want to.
• The filling for this pie will be fully cooked at a temperature of 160 to 180 degrees F. The pie will seem loose and jiggly when you take it out of the oven, but that’s OK. It will set up as it cools (especially in the fridge). Do not overbake this pie—it will crack and dry out quickly if you do.
• An instant-read thermometer is perfect for checking the internal temperature of almost anything you bake or cook. Most of the ones you can buy are accurate, although some may take 10 or 15 seconds to record temperatures. Our favorite instant-read thermometer is the Thermapen. These are accurate to less than 1 degree F, and take a reading in 3 seconds or less. The downside? They’re pricey (about $90 or so). But they’re worth it.
• If you don’t have an instant-read thermometer, you can eyeball the pie filling for doneness. It should look “set” around the edges, but the middle two or three inches should still be jiggly.
• This pie is wonderful all by itself, but a topping of ice cream or whipped cream is delicious.
• Want to make rum-flavored whipped cream? Here’s our technique: Pour 2 cups of heavy whipping cream into the bowl of a stand mixer (or into a large mixing bowl, if using a hand mixer). Add about three tablespoons of powdered sugar and 1 tablespoon of dark rum. Begin to whip on low speed. Increase to medium as soon as you can (i.e., when the cream is becoming thick enough that droplets don’t spatter from the mixing action). Beat the cream until it forms soft peaks, then taste and add more sugar and/or rum if necessary. Continue beating until you reach the medium or stiff peak stage (whichever you prefer). Refrigerate the whipped cream if it’s going to be sitting for more than a few minutes before you serve it (don’t worry, it won’t collapse).

Traditions, Old and New

“I can’t believe I’m saying this, because I love pumpkin pie,” said Mrs. Kitchen Riffs. “But this Sweet Potato Pie is way better.”

“For sure,” I agreed. “Amazing that it’s taken us so long to perfect our own recipe for it.”

“Probably because pumpkin is so good,” said Mrs K R. “And there’s that tradition thing, too—including our own.”

“Easy to get stuck in a rut,” I said. “Say, remember the plan we talked about after our first piece of Sweet Potato Pie, way back when? The one we wrote about in our last post on Sweet Potato and Rosemary Casserole?”

“Yup, when we stopped in De Valls Bluff, Arkansas to try the great barbecue place that Jane and Michael Stern of Roadfood fame wrote about,” said Mrs K R.

“And across the street was the Family Pie Shop,” I added. “Another of their recommendations.”

“That’s when we realized what a great combo pie and barbecue make,” said Mrs K R. “And we decided that someday we should take a pie-and-barbecue tour of the US.”

“Yeah, traveling from coast to coast, stopping to sample pie and Q everywhere,” I said. “Too bad we never got around to doing that.”

“Maybe one of these days,” said Mrs K R. “But right now we’ve got this nice, big Sweet Potato Pie to finish right here.”

“And as it happens, we can walk to a pretty good barbecue place in our current neighborhood,” I added.

“Maybe we should get some takeout for dinner tonight,” said Mrs K R. “And next time I bake Sweet Potato Pie, you can make your dynamite Oven Slow-Cooked BBQ Spare Ribs.”

Great idea. Sometimes the best roadfood is right at home.

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Black Walnut Sandies
Grape Flaugnarde (Flan)
Roast Sweet Potatoes
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