Transform your holiday table with this irresistible Boston Market Sweet Potato Casserole that combines the best of comfort food in one dish! This copycat recipe captures the restaurant’s signature combination of creamy, spiced sweet potatoes topped with fluffy marshmallows and a golden oatmeal cookie-like crust.
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Why this recipe works
The magic happens in three distinct layers that complement each other perfectly. The sweet potato base gets its luxurious texture from proper roasting and mashing with butter and cream, while warm spices add depth without overwhelming the natural sweetness. The marshmallow layer provides that nostalgic comfort food element, and the oatmeal crust delivers a satisfying crunch that contrasts beautifully with the soft interior. This combination creates a dish that’s both elegant enough for special occasions and comforting enough for everyday enjoyment.
Ingredients
For the Sweet Potato Base:
- Sweet potatoes – Provide the creamy, naturally sweet foundation of the dish
- Butter – Adds richness and helps create smooth, luxurious texture
- Eggs – Bind ingredients together and create a custard-like consistency
- Salt – Enhances natural sweetness and balances all flavors
- Ground cinnamon – Adds warmth and classic holiday spice notes
- Ground nutmeg – Contributes aromatic depth and complexity
- Vanilla extract – Enhances sweetness and adds aromatic richness
- Dark brown sugar – Provides molasses notes and deeper sweetness
- Heavy cream – Creates ultra-smooth, restaurant-quality texture
For the Oatmeal Crust:
- All-purpose flour – Forms the base structure of the crunchy topping
- Quick-cooking oats – Creates a signature texture and nutty flavor
- Dark brown sugar – Sweetens the crust and helps with browning
- Butter – Creates a crumbly texture when worked into dry ingredients
- Ground cinnamon – Unifies flavors throughout the dish
- Salt – Enhances the crust flavors and balances the sweetness
For Assembly:
- Miniature marshmallows – Provide the classic sweet, gooey middle layer
How to Make Boston Market Sweet Potato Casserole
- Wrap sweet potatoes in foil, place them on a baking sheet, and bake at 350 degrees for about an hour, until they are easily pierced with a fork.
- Allow the sweet potatoes to cool until they are cool enough to handle.
- Remove the foil and sweet potato, then remove the skins.
- Place the cooked sweet potatoes into a large bowl.
- Mash the sweet potatoes with butter until mostly smooth.
- Add eggs, salt, cinnamon, vanilla, and nutmeg, and beat until a uniform mixture forms.
- Add brown sugar and cream and mix well.
- Combine the flour, brown sugar, salt, oats, and cinnamon in a medium bowl and stir until well combined.
- Stir in butter with a fork until you have a crumbly mixture.
- Lightly coat a 9×13-inch baking pan with cooking spray.
- Spread the sweet potatoes in the pan.
- Top with the marshmallows, then crumble the oatmeal crust on top of the marshmallows.
- Bake at 350°F for 30 to 45 minutes.
Make-ahead Strategy
For optimal results, bake the casserole thoroughly and then refrigerate. Reheat gently in the oven the next day. The raw eggs make it inadvisable to assemble and refrigerate an unbaked casserole overnight, as this affects both safety and texture.
Storage & reheating instructions
- Refrigerator Storage: Store covered casserole in refrigerator for up to 4 days after baking
- Reheating Method: Reheat covered in a 350°F oven for 20-25 minutes until heated through. For a crispier top, uncover for the last 5 minutes of reheating.
- Freezing: Wrap tightly and freeze for up to 3 months. Thaw completely before reheating.
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Boston Market Sweet Potato Casserole Copycat Recipe
Ingredients
Sweet Potato Layer
- 5 pounds sweet potatoes
- 4 tablespoons butter
- 2 eggs slightly beaten
- 1 teaspoon salt
- 1 teaspoon ground cinnamon
- 1/2 teaspoon vanilla extract
- 1/2 teaspoon ground nutmeg
- 1/2 cup dark brown sugar
- 1/4 cup heavy cream
- Nonstick cooking spray
Cookie Crust Layer
- 1/2 cup all-purpose flour
- 1 cup dark brown sugar
- 1/4 teaspoon salt
- 1 cup quick-cooking oats
- 1/2 teaspoon ground cinnamon
- 1/4 pound butter
- 2 cups miniature marshmallows
Instructions
Sweet Potato Layer
- Preheat the oven to 350 degrees F.
- Wrap sweet potatoes in foil, place them on a baking sheet and bake for about 1 hour. After 1 hour, test by piercing with a fork; if you can pierce them easily, they are done baking. If not, bake them a little longer and test again. Allow the sweet potatoes to cool until you can handle them, remove foil, and remove skins by simply pushing off the skins from the flesh of the potato.
- Place the cooked potatoes into a large bowl. If using canned sweet potatoes, skip the baking. Just open the cans and drain off the syrup. Mash the sweet potatoes with the butter using a pastry blender or a potato masher until mostly smooth.
- Add the eggs, salt, cinnamon, vanilla, and nutmeg and beat until you have a uniform mixture. Add the brown sugar and cream and mix well.
Oatmeal Cookie Crust
- Combine the flour, brown sugar, salt, oats, and cinnamon in a medium bowl and stir together well. Stir in the 1/4 pound butter with a fork until you have a crumbly mixture.
Casserole
- If you had turned off the oven, heat it again to 350 degrees F. Lightly coat a 9 x 13-inch baking pan with cooking spray.
- Spread the sweet potatoes in the pan. Top with the marshmallows, then crumble the oatmeal crust on top of the marshmallows. Bake 30 to 45 minutes.
Video
Nutrition
About Boston Market
As everyone knows, Boston Market is not just in Boston. It’s a chain of fast-casual stores that specializes in rotisserie chicken and other meat dishes, along with a choice of sides. However, the founders, Arthur Cores and Steven Kolow, did reside in Boston.
Their concept was to provide food that was fresh and healthy but delivered quickly at prices closer to those of your typical fast food.
I make this every year. Best sweet potato casserole recipe by far
I would love to make this sweet potato casserole in a crock pot to stay warm until dinner is that possible and would that cool on high or low for how long and what adjustments of any to recipe should I make?
Thank you so much!
I don’t think the topping is going to get crisp in a crockpot.
Why is it called a cookie crust when it is put on top of the sweet potatoes
Because it is essentially a cookie batter on top of the sweet potatoes.
Could i use a fourth of cream cheese for the heavy cream in the sweet potato layer?
I don’t think that would work because you need the liquid of the heavy cream. I haven’t tested any modifications, but if I was going for a reduction in calories why not swap it for half and half?
Have been using this recipe in my home for years. Has never failed me and never failed to get raving reviews! THE best!
I give this a 4.5 out of five. Delicious!! I used the canned sweet potatoes/yams so it came out a bit runny but did not affect the taste at all. Very easy to follow and a perfect replacement to the Boston Market side.
Next time pJour the liquids from the can out, not into the recipe.
Hi! I’ve made this many times and love it! But i started to have a sensitivity to eggs. Would it still work the same if I just omitted the eggs and still followed the rest of the recipe?
Thanks for the recipes Stephanie! Do you think I’d be ok to freeze this dish after I make it? My brother gave me a box of sweet potatoes as a gag gift for my birthday, and my husband and I won’t be able to eat a whole box before it goes bad. I hate seeing food go bad ☹️
I need to make this the night before and bake it before dinner… Can I refrigerate the crumb topping after I’ve mixed all the ingredients? Thanks for any advice.
I am not certain of the results if you do this. Flour tends to change over a long refrigeratoration.
Sure, this should work. You might just want to bake it, and reheat it.
I made this for Thanksgiving. It was amazing! Everyone loved it. Even non sweet potato eaters loved it. It tastes better than Boston Markets.
I’ve made this recipe quite a few times, and it’s always a big hit with everyone! Thanks for sharing it with us! I do have a question though, since I lost my recipe. When I looked up this one again, your recipe directions and ingredients say 4 Tbsp (1/2 stick) of butter with the potato mixture and 1 whole stick for the cookie topping, but in your comments and responses, you say 1/2 stick in the potato mixture and 1/2 stick in the crumble mixture, so I’m kind of confused of which way I should follow. I believe when I’ve made it in the past, I used 1/2 stick in the potatoes and 1 whole stick in the cookie topping, but now I’m questioning that. Can you please let us know which way is the right one and possibly update the right one? I’m going with the actual directions since that’s the way I think I made it in the past, but the other comments may confuse people. Thanks again for giving us this amazing recipe! Happy Thanksgiving!
I noticed that too, I made it last week for an early thanksgiving gathering following the recipe, and it turned out great. I am making it again today using the 1 stick of butter in both the potatoes and the topping. I can’t see it hurting any.
Please use the directions as written. It’s 4 tablespoons for the potatoes and a stick for the oatmeal cookie crumb topping.
Hey I used half a stick of butter and then used cream cheese for the rest. No particular measurements, just by taste and texture. Kept adding. I added pumpkin spice too, just a little. I also used a little bit of granulated sugar, brown sugar was a tad bland for me. ✋Great recipe, I’m here for the holidays.
Can you freeze the base uncooked or should I️ cook the base and then freeze
Hello, I am from Quebec City. I don’t think we have oatmeal cookie crust ar the supermarket. What can I do to replace this ingredient?
The ingredients listed under the cookie crust line are what you put in the crumble…see directions.
Stephanie, this recipe is absolutely fabulous!! Every year I try to make sweet potato casserole and I’m never happy. My husband’s favorite is Boston Market’s SP casserole. So, I thought, I’ll just buy them. Cost was $80. No thanks. I made 1 1/2 times this recipe to feed the group. Everyone loved it. And best of all, my husband said it was better than Boston Market’s!!! Will make every year from here on out. Kudos to you!!! Thank you so much!
Well I am glad I could help you make Thanksgiving cost a little less.
I prepared this recipe and I have to say it was very delicious. It was very easy to make as well. I loved how easy the jackets came off after baking vs boiling the potatoes.
I will be using this recipe every year because it is easy and delicious !
Thank you so much !