How to Make Creamy Purple Mashed Sweet Potatoes (Easy, Vibrant, Holiday-Ready)

Not your average spuds!
These Mashed Purple Sweet Potatoes will light up your holiday table. Their bold purple color isn’t just for show; it’s a sign they’re packed with antioxidants and naturally sweet flavor. Made with murasaki imo, a touch of grass-fed butter, and creamy coconut cream, they’re rich, vibrant, and unforgettable. One bite, and you’ll never go back to plain mashed potatoes.

This purple sweet potato recipe shows you how to make creamy mashed Japanese murasaki imo, and explains what purple sweet potatoes are, how they taste, and the best ways to cook them.

Full disclosure: I never loved mashed potatoes growing up in the US. They were fine, on the side. Tradition is tradition, and they go with turkey. But let’s be honest, even with gravy, regular mashed potatoes only get so good.

I didn’t grow up eating Japanese sweet potatoes, and definitely not the purple ones. But after living in Japan for over 20 years, I crave them the way my inner American child craves french fries.

You’re in for something special. That mashed potato ceiling? Consider it shattered.

Got a question or need help finding murasaki imo? Leave a comment below. I personally respond to every message.

❤️ from Japan,
Matt

Why You'll Love These Mashed Purple Potatoes

These mashed Japanese sweet potatoes are more than just colorful. They’re creamy, naturally sweet, and surprisingly simple to make. Whether you're hosting a holiday meal or cooking a cozy dinner at home, here’s what makes this recipe special:

Vibrant and eye-catching
The bold purple color brings personality to your table and makes any meal feel festive.

Creamy and comforting
Coconut cream and a touch of butter create a rich, silky texture that feels indulgent in every bite.

Naturally sweet and nutrient-rich
Murasaki imo are full of flavor, fiber, and antioxidants. No added sugar needed.

Simple and satisfying
Roast, mash, mix, and serve. No peeling or fancy tools required.

Unexpectedly crowd-pleasing
Even mashed potato traditionalists will ask for seconds.

Dairy-optional and flexible
Use grass-fed butter or keep it completely plant-based. It’s just as delicious with regular satsumaimo too.

Craving something crispy instead? Try my Japanese-Style Air Fryer Purple Sweet Potato Fries. They're golden, crunchy, and just as easy to make.

Ingredients You'll Need

• Japanese sweet potatoes (purple or regular satsumaimo)
• Grass-fed butter (or plant-based butter for a dairy-free option)
• Coconut cream (or coconut milk if you can’t find cream; it will be a bit lighter)
• Sea salt
• Black pepper
• Honey (optional, adds natural sweetness)
• Organic lemon peel (optional, adds fresh flavor and a pop of color)

Kitchen Tools

• A sharp knife and cutting board for prepping the sweet potatoes.
• Aluminum foil to wrap the potatoes while baking.
• Oven for baking at 320°F.
• A potato masher, fork, spoon, or spatula—any tool you prefer for mashing.
• Frying pan to melt butter, mash the potatoes, and mix in coconut cream and seasoning.
• Optional: a zester if you’re adding lemon peel for garnish.

Where to buy Japanese sweet potatoes?

In Japan, Japanese sweet potatoes are easy to find at most supermarkets during the fall and winter.

In the United States and other countries, they can take a little more effort to track down, but they’re becoming more common. Farmers in North America now grow varieties like murasaki sweet potatoes and Stokes sweet potatoes. Stokes originated in North Carolina and are now grown in California as well.

Start by checking Japanese grocery stores like Nijiya Market or your local Asian supermarket. Trader Joe’s sometimes carries them as a seasonal item.

For organic options, try Whole Foods or a local co-op. You might also have luck at a farmer’s market. Ask around—farmers are often a great source of information.

If you don’t live near a major city, you may need to order online or substitute a local variety of sweet potato.

What are Japanese sweet potatoes?

Japanese sweet potatoes, known as satsumaimo (さつまいも), are a beloved variety of sweet potato in Japan, especially during the fall and winter. They’re naturally sweet, dense, and creamy, with a flavor and texture noticeably different from the orange-fleshed sweet potatoes common in the West.

Funny enough, “Japanese” sweet potatoes didn’t originate in Japan. They were introduced from Central or South America via China in the 17th century and took root in what’s now Kagoshima Prefecture. Today, that southern region remains one of Japan’s top producers of satsumaimo.

On the outside, satsumaimo have reddish-purple skin. When sliced open, the flesh is pale yellow or cream-colored, sometimes with a hint of orange. Once cooked, it turns golden and develops a rich, slightly flaky texture. Unlike orange sweet potatoes, they aren’t watery and hold their shape well.

In Japanese kitchens, you’ll find them baked, steamed, simmered, fried, or candied. They also show up in seasonal sweets and snacks, from mochi to ice cream.

What do Japanese sweet potatoes taste like?

Satsumaimo have a naturally earthy, nutty flavor and a dense, creamy texture similar to baked potatoes, only creamier. When baked, they become a dessert on their own. Their subtle sweetness is reminiscent of chestnuts, caramel, or a rich pumpkin pie filling, but milder.

The warm, comforting aroma of a freshly baked satsumaimo is like "chestnuts roasting on an open fire," instantly evoking nostalgic memories for many Japanese people. Walking past a yaki imo truck in Tokyo is like passing a Cinnabon in a mall—an irresistible scent that pulls you in every time.

What are purple Japanese sweet potatoes?

In Japan, purple sweet potatoes are called murasaki imo (紫芋). Murasaki imo have reddish purple, brownish purple, or purple-colored skin. When I sliced into one for the first time, I was surprised by just how vibrant purple it was on the inside. 

It’s anthocyanin, a chemical compound, that gives them their purple color. One reason they’ve gained popularity is their striking appearance and naturally high antioxidant content.

Even after being cooked, they stay the same bright, beautiful purple color. If cooked correctly, you'll get a soft, creamy texture.  

On the outside, murasaki imo look quite similar to other satsumaimo. When you take a bite, you’ll notice they’re less sweet than regular satsumaimo or orange sweet potatoes, with a drier, more starchy texture.

They're easily confused with Okinawan sweet potatoes. Okinawan sweet potatoes are also purple on the inside but have a pale white-colored skin.

Murasaki imo were originally cultivated in the south of Japan. Now, they're mostly grown in Kagoshima Prefecture and Okinawa.

Even though the variety is not as sweet, murasaki imo are a popular choice. In addition to home cooking, they’re used to make packaged snacks, bright purple chips, and desserts. 

If you want a crispier preparation, try my Japanese-style purple sweet potato fries.

What do purple Japanese sweet potatoes taste like?

Murasaki imo, purple Japanese sweet potatoes, are not as sweet. But believe me, they're still sweet.

When baked, you still get that same creamy bite. It's just slightly drier and starchier.

Why are Japanese sweet potatoes healthy?

There are lots of health benefits to adding Japanese sweet potato to your diet. During the fall and winter, I eat satsuma-imo multiple times a week instead of rice or grains.

Japanese sweet potatoes are rich in vitamins, minerals, and dietary fiber. Compared to white potatoes, sweet potatoes contain more vitamin C. Satsumaimo are also a good source of vitamin A, potassium, copper, and manganese.

According to Rumi Nakazawa, a registered dietitian, Japanese sweet potatoes have 10 times more vitamin C than apples. The vitamin C in Japanese sweet potatoes, in addition to boosting your immune system, also promotes healthy skin. Vitamin C is an essential element in making collagen, which makes your skin firmer.

Like other sweet potatoes, satsumaimo contain antioxidants such as beta-carotene.

While all sweet potatoes are high in complex carbohydrates, the carbohydrates in satsumaimo have a relatively low glycemic index (GI). The GI of Japanese sweet potatoes depends on your cooking method. For a lower GI, boil them instead of baking at higher temperatures, which breaks down the starches into sugar.

What's more, the dietary fiber in Japanese sweet potatoes may support healthy digestion and satiety.

Are purple sweet potatoes healthier?

As a general rule, the more vibrant the color of the potato's flesh, the more nutrition it contains. 

Like blueberries, sweet potatoes that are purple on the inside contain anthocyanins. 

Anthocyanins are a type of antioxidant commonly associated with a variety of health benefits.

Purple sweet potatoes have a lower glycemic index (GI) than orange sweet potatoes.

All sweet potatoes are high in carbohydrates. Eating them can spike blood sugar levels. Despite their nutrition powerhouse superfood status, I keep my portion size relatively small.

What to serve with mashed Japanese sweet potatoes:

Tradition is tradition. But why not add a little color to your Thanksgiving dinner? 

You don't need to replace your regular mashed potatoes and gravy!

I do, however, recommend these purple mashed potatoes to go with your turkey.