Kyoto Style Sweet Potatoes

If sweet and salty is your thing, then these Kyoto Style Sweet Potatoes glazed in a sweet miso butter sauce are sure to hit the spot. 

The sweet sauce is brushed on top of roasted Japanese sweet potatoes and then broiled in the oven, resulting in a caramelized crust on top of the fluffy, fork tender sweet potatoes. It’s a really nice combination of textures. 

And even though these potatoes are a side dish, they’re so packed with flavor that they can easily be eaten with some rice as a main course. 

What are Kyoto Style Sweet Potatoes?

Kyoto Style Sweet Potatoes are a side dish of Japanese sweet potatoes topped with a sweet miso butter glaze.

This recipe uses Japanese sweet potatoes, the sweeter, fluffier alternative to the regular orange variety.  Although you could easily substitute orange sweet potatoes in this recipe if that’s all you can find.

The potatoes are first roasted in the oven without the sauce.  After they’re done roasting, the potatoes are topped with the miso butter sauce and then broiled to caramelize the sauce.

Although this dish is simple to make, it packs a ton of flavor.

How are Japanese sweet potatoes different?

Japanese sweet potatoes have purple skin and an off-white flesh that turns a darker shade of yellow once cooked.

The Japanese variety of sweet potato is much sweeter than other orange flesh sweet potatoes or yams typically found in the US.  The flavor has a nutty quality that’s reminiscent of chestnuts. Since it’s so sweet, it’s used often to make desserts like this traditional sweet potato dessert.  

Their texture is a bit more dry and starchier than orange sweet potatoes.  The consistency is actually more similar to white Russet baking potatoes than orange sweet potatoes.  This means that your Japanese sweet potatoes will be a bit fluffier and lighter-feeling than the orange ones.

Japanese sweet potatoes are becoming more and more available in the US.  Whole Foods carries them and so does Trader Joe’s (under the name “Murasaki sweet potato”).  

If you can’t find the Japanese variety, the orange sweet potatoes can be used for a substitute in certain cases, such as in this recipe. 

Ingredients

Japanese sweet potatoes.  These uber sweet, fluffy potatoes pair perfectly with the sweet and salty miso glaze.

Miso.  Miso is the base for the sauce, providing complex flavors of umami, saltiness, funkiness and some sweetness. I prefer red miso in this recipe because it has a deep, strong flavor that stands up to the sweetness. Though any other kind of miso, such as a milder white, would work fine.

Sake.  Sake is the secret ingredient to so many Japanese recipes, enhancing the overall flavor of the dish and adding some umami and sweetness.  

Mirin.  Mirin is often used with sake in Japanese sauces, and we’ll use it here.  It adds more subtle sweetness to the sauce and compliments the sake.

Sugar.  A bit of sugar provides even more sweetness.

Butter.  Butter rounds out the sauce, providing richness and creaminess.

Scallions.  A pop of scallions garnish the dish, giving it some oniony bite.

Sesame seeds.  Sesame seeds also garnish the dish, providing just a bit of nuttiness that compliments the sweet potatoes.

Can I substitute orange sweet potatoes for the Japanese ones?

The orange-fleshed sweet potatoes or yams that are more accessible in the US can easily be used as a substitute in this recipe. 

The potatoes won’t be as sweet and their texture won’t be as fluffy, but they’ll still taste great. 

What kind of miso should I use?

Red miso is preferable for this recipe, since it has a deep, rich flavor that stands up to the sweetness of the sauce and the potatoes.

Though you can use any kind of miso paste, such as the milder white miso, and the potatoes will still taste great. They’ll just have a less strong miso flavor.

How to make Kyoto Style Sweet Potatoes

1. Bake the potatoes.  Slice the potatoes in half lengthwise and rub two tablespoons of a neutral oil on both sides of the potatoes.  Place the potatoes on a foil-lined sheet tray, cut side down, and bake at 350° for 30-35 minutes.
2. Make the sauce.  While the potatoes are roasting, mix the miso paste, sake, mirin and sugar in a small bowl until combined.  Cook the sauce in a small saucepan over medium-low heat for 5 minutes, stirring very frequently to prevent scorching.  Next add the butter, and continue cooking for 3 more minutes, stirring frequently.
3. Glaze and broil the potatoes.  Once the potatoes are finished baking, remove them from the oven and turn your oven’s broiler to high heat.  Flip the potatoes over on the sheet pan so that they’re cut side up.  Use a pastry brush to apply the sauce on top of the potato flesh.  Now broil them in the oven for 1-3 minutes until the glaze is beginning to caramelize.  Check the potatoes frequently to avoid burning them.

Tips for making Kyoto style sweet potatoes

1. Cut the potatoes in even halves.  When you slice the potatoes lengthwise, make sure that they’re cut right down the middle into two equal portions.  This ensures that both sides of the potato require the same amount of time for roasting and they’ll all be finished at the same time.
2. Stir the sauce very often while cooking.  Since this sauce has a high sugar content, it can burn very quickly.  So while you’re cooking it on the stove top, make sure to stir it very frequently.  And while you’re stirring it, ensure that you scrape the sauce from the bottom of the pan so that it doesn’t burn. 
3. Keep a close eye while broiling.  The broiling process caramelizes the sauce on top of the potatoes, bringing out the sweetness and giving the potatoes a nice, lightly crispy crust.  But since the sauce has such a high sugar content, it can burn very quickly.  So keep a very close eye on your potatoes when you do the broiling.  Depending on the strength of your oven’s broiler, it could take only one minute to caramelize and could begin burning right after that.

What to serve Kyoto Style Sweet Potatoes

These sweet potatoes are a pretty versatile side dish that can be served with many different types of main courses.

They would obviously go great with other Japanese-inspired dishes (like this sushi bake), but are flexible enough to be served with other types of foods like Korean or even American food.

Since the potatoes are so sweet, they would go extremely well with something spicy and acidic, like these loaded kimchi fries topped with spicy mayo, jalapenos, and fresh lime.

And since these potatoes are so good, I’ve eaten them as a main course with rice on the side.