This recipe for miso butter Japanese sweet potatoes will up your baked potato game! If you’ve never tried a baked Japanese sweet potato before, this simple recipe for sweet, starchy baked potatoes slathered with a simple compound butter and topped with herbs is sure to become a favorite.

Baked Japanese Sweet Potato with Miso Butter

A simple baked potato is one of the most crowd pleasing side dishes, especially when it’s done right. Who doesn’t love that moist, fluffy interior, especially when it’s slathered with plenty of butter - any maybe some bacon bits and scallions for good measure!

What’s tastier than a simple, baked russet potato? A baked sweet potato, with its rich, sweet flavor. But did you know it can get even better than that? A baked Japanese sweet potato. Now, imho, that is baked potato perfection!

Have you ever had a Japanese sweet potato? Murasaki sweet potatoes, or Japanese sweet potatoes, are my personal favorite starchy tuber. Topped with miso butter and a hearty sprinkle of fresh herbs, this baked Japanese sweet potato recipe is your new favorite side dish.

What are Japanese sweet potatoes?

A Japanese sweet potato is a type of sweet potato that is commonly consumed in Japan, although the most common type of Japanese sweet potato, a Murasaki sweet potato, is a relatively new variety that was developed in Louisiana. They have purple skin and a creamy, yellowish flesh. A baked Japanese sweet potato has the most incredible texture. It’s dried, starchier and yet creamier than a regular sweet potato. While they still taste sweet, they have a much more complex, earthy flavor. It almost tastes similar to chestnuts!

In Japan, you can get a baked Japanese sweet potato often served plain as a snack, especially in autumn. When I traveled to Japan in 2017, I found they were also commonly served in braised dishes and stews. My favorite Japanese cookbook, Japanese Cooking: A SImple Art, has a recipe for Japanese sweet potatoes simmered in miso that is soooo delicious.

Easy Baked Japanese Sweet Potato with Miso Butter

Nutritionally, Japanese sweet potatoes are similar to common sweet potatoes in terms of carbohydrate and fiber content. They do contain a little less carotenoids, since they don’t have the bright orange (i.e. carotenoid-rich) flesh of a common sweet potato, but still have a nice dose, along with b vitamins and bone-building minerals.

How to make a baked Japanese sweet potato

There’s a few different ways to bake a Japanese sweet potato, and from my google research, it looks like the big debate is between wrapping it in foil vs. baking it naked. I am team naked. The foil keeps more moisture in, but it’s sweeter when you bake Japanese sweet potato naked. That’s because it allows some of the moisture to escape, which helps concentrate the flavor a bit. Don’t worry though - it won’t dry out too much as long as you just poke a few holes in the flesh with the tines of a fork (rather than massacring it, Freddy Kruger-style as my husband did the last time he made us sweet potatoes) and rub it with some oil, which also helps keep moisture in.

Simple Baked Japanese Sweet Potato with Miso Butter

To make a baked Japanese sweet potato, preheat the oven to 425 degrees F. Poke the sweet potato with the tines of a fork a few times on each side, rub with a bit of olive oil, and bake until it’s tender when you stick a sharp knife into it, about 45-55 minutes. If the potatoes are thinner, check at around 30 minutes. Since potatoes can vary in thickness quite a bit.

How to make miso butter for baked Japanese sweet potatoes

What sets this recipe for baked Japanese sweet potato apart is the simple miso butter it’s slathered with. Made with equal parts unsalted butter and miso paste, smashed together at room temperature, it couldn’t be simpler to make. I would suggest doubling up the miso butter and saving some in the fridge. If you do, here’s some tasty ways to use it:

Spread over toast, especially toasted Japanese milk bread.
Toss with roasted veggies, like roasted Brussels sprouts, carrots, or green beans.
Use it to sauté greens, like spinach or bok choy
Melt some into a bowl of white beans, like in this recipe for brothy white beans with scallions.
Try a spin on buttered noodles by tossing hot cooked soba noodles with miso butter.
Spoon some over salmon then slow cook in the oven
Top grilled steak with a spoon of miso butter
Melt miso butter and pour over freshly popped popcorn. I bet my nori popcorn would be delicious with it!

Serving suggestions for baked Japanese sweet potato with miso butter:

This recipe for baked Japanese sweet potatoes with miso butter would pair well with the following:

Miso glazed salmon and sesame sauteed spinach
Yakitori grilled chicken and vegetables
Teriyaki tofu (my favorite teriyaki sauce is Bachan's - I'm biased because my brother-in-law's friend from high school started it and we've been stocking up on it from California since way before it went mainstream) and sauteed mushrooms.
Japanese eggplant with scallions and ginger and grilled flank steak (try my garlic and ginger marinated flank steak)

To serve these baked Japanese sweet potatoes, I like to garnish them with chopped fresh scallions and cilantro, and a pinch of shichimi togarashi, a Japanese spice mix with shichimi, a tingly spicy red pepper, sesame, and orange peel.

If you like this recipe for baked Japanese sweet potato with miso butter, follow my Pinterest board for easy, healthy potato recipes for more cooking inspiration.

This recipe for baked Japanese sweet potato with miso butter has been updated since publication in March 2017 to give you the best possible content.

Baked Japanese Sweet Potato with Miso Butter Recipe

Makes 6 halves

Ingredients

3 large purple sweet potatoes
1 teaspoon olive oil
3 tablespoons butter, room temperature
3 tablespoons miso paste, any kind
Chopped fresh cilantro and green onions, for serving
Shichimi togarashi, optional, for garnish

Directions

Preheat oven to 375 degrees F.
Prick sweet potatoes all over with the tines of a fork. Rub all over with olive oil. Wrap each sweet potato with a square of aluminum foil and place in the oven. Bake 45-55 minutes until potatoes are tender. You may want to check at 30 minutes if your potatoes are on the smaller side. You can check for doneness by squeezing with an oven mitt protected hand or inserting a knife into the wrapped potato. It should go in easily.
While potatoes are baking, mix together butter and miso paste with a fork until well combined. Refrigerate until ready to use.
When potatoes are baked, remove from oven and let cool slightly. Cut in half and top with a hefty dollop of miso butter. Garnish with scallions and cilantro.