Easy classic sweet potato casserole made with only 6 ingredients. Topped with mini marshmallows and perfectly sweet, this recipe is sure to be a family favorite.
Sweet potato casserole has always been my favorite dish! My mom made it at least three times a year growing up and I was always a huge fan. Her version has a brown sugar pecan topping (see my healthy sweet potato casserole) but Isaac grew up with traditional sweet potato casserole with mini marshmallows on top.
Without fail, every year Isaac requests the classic version so I finally decided to give it a go and… whoa, it turned out to be so delicious! I am honestly kind of surprised at how much I liked this version. Usually I’m all about the crunch of the pecan topping. That said, the marshmallows actually get a little crisp with this version so maybe that’s why I’m a fan.
Classic Sweet Potato Casserole Ingredients
You only need 6 simple ingredients for this traditional sweet potato casserole! I didn’t make any healthy subs for this recipe… well, except for the coconut sugar! I did use real deal (organic) butter and regular mini marshmallows, but you could easily make this dairy-free and vegan by using vegan butter (or coconut oil) and vegan marshmallows.
coconut sugar – light brown sugar works too.
unsalted butter – use vegan butter or coconut oil if needed.
miniature marshmallows – I used regular, but vegan marshmallows will also work. Try the Dandie’s brand.
Buying & Storing Sweet Potatoes
When shopping for sweet potatoes, look for firm, unwrinkled skins. Sweet potatoes come in all different colors – creamy white, deep orange and purple. I usually buy Beauregard, Jewel or Garnet sweet potatoes just because those varieties are typically available at my local grocery stores. That said, Beauregard sweet potatoes tend to be stringier so when given the option I go for Jewel or Garnet.
Store you sweet potatoes in your pantry or on the counter top at room temperature. They’ll last about a week before they start to go bad (which usually means getting wrinkly and soft).
4 Ways to Cook Sweet Potatoes Before Mashing
Bake – Pierce the sweet potato 4-6 times with a fork. Place potato on a baking sheet and bake at 400ºF for about 45-65 minutes.
Boil – Peel and cube the sweet potatoes. Place in a large saucepan and add water to cover the potatoes. Bring to a boil, reduce heat and cook, uncovered until tender. It should take about 15 minutes depending on the size.
Microwave – Pierce the sweet potatoes 3-4 times with a fork. Place potatoes in a microwave-safe dish and microwave on high for five minutes, flipping halfway through. If your potatoes aren’t tender after 5 minutes, microwave for 30 second increments until softened. I personally don’t recommend this method because microwaved sweet potatoes don’t taste great, in my opinion.
Instant Pot – Add one cup of water to the bottom of your Instant Pot. Place the trivet on top and then the sweet potatoes on the trivet. Cook for 18 minutes on high pressure (for medium-sized potatoes), let naturally steam naturally release for 10 minutes and then quick release any remaining pressure.
How to make Traditional Sweet Potato Casserole
Classic sweet potato casserole is so dang easy to make. Here’s how:
Cook sweet potatoes – Use any of the methods listed above to cook your sweet potatoes prior to mashing. Measure out 6 cups of mashed sweet potato.
Combine – Place the mashed sweet potatoes in a large bowl. Add sugar, softened butter, salt and vanilla. Stir to combine or use a stand mixer to mix well.
Bake – Transfer the sweet potato mixture into a 9 x 9 inch baking dish coated with cooking spray. Use a spoon to spread mixture evenly. Top with marshmallows and bake at 375ºF for 20-25 minutes or until marshmallows are golden brown.
How to Make Sweet Potato Casserole Ahead of Time
You can certainly prep this sweet potato casserole ahead of time to make things easier for holiday meals!
One option is to cook your sweet potatoes in advance. Once cooked, let cool and store in the fridge for up to 3 days before making the casserole.
Another option is to prep the recipe according to the instructions through step four, cover the casserole dish with foil or plastic wrap and keep in the fridge for 1-2 days. On the day of serving, bring the dish out and let it come to room temp (about 10-15 minutes), top with marshmallows and bake ins 375°F oven for 20-25 minutes or until potatoes are warm and marshmallows are golden.
Bake sweet potatoes: Heat oven to 400°F. Pierce sweet potatoes with a fork several times. place sweet potatoes on baking sheet. Roast 1 hour or until tender. Let cool and remove skin from the sweet potatoes and discard. Place flesh into medium bowl, mash with a fork and measure 6 cups. Save any extra for another use.
Reduce oven temperature to 375° F.
Combine: Place mashed sweet potatoes in a large bowl. Add sugar, softened butter, salt and vanilla. Stir to combine. You can do this in a stand mixer if you’d like.
Transfer sweet potato mixture into a 9 x 9-inch baking dish coated with cooking spray. Use a spoon to make sure the mixture is evenly distributed.
Bake: Top with marshmallows and bake for 20-25 minutes or until marshmallows are golden. Serve warm.
You can also boil the sweet potatoes if you prefer. To do so, peel and cube sweet potatoes. Place in a large saucepan; add water to cover. Bring to a boil. Reduce heat; cook, uncovered, until tender, 15 minutes, depending on size. Drain potatoes, mash and measure 6 cups for the recipe.
If you’re like me and love pecans, you can sprinkle 1/4 cup pecans on top of the sweet potato mixture with the marshmallows.