New potatoes with butter and soy sauce (Shinjaga shouyu bataa)


We live in a semi-rural area (well, most areas outside of the cities are semi-rural in Switzerland) and one of the things grown here locally are potatoes. While most farmers like to grow those potatoes until they are quite huge, around this time we can get tiny new potatoes. I love new potatoes - they have a fresh, very slightly mineral-y flavor to them which is quite different from mature potatoes.

If you're not familiar with new potatoes, try to get organically grown ones. This way you can eat them skin and all - peeling those really tiny potatoes can be a bit of a pain. The skins of fresh new potatoes should pale and very thin.

The easiest thing to do to new potatoes is to simply boil them and eat them with salt, pepper and a little butter or crème fraîche. This Japanese-flavor recipe is almost as easy though. Soy sauce and butter go marvelously well together, and enhance the new potatoes in a very satisfying way. In Japan the new potatoes would be deep-fried to get them crispy, but I've oven-baked them instead to cut down somewhat on the fat. (New potatoes in Japanese are called shinjaga (新じゃが)).

Recipe: New potatoes with butter and soy sauce (Shinjaga shouyu bataa)

  • About 500g / 1 lb tiny organic new potatoes, washed and unpeeled
  • Salt
  • 2 Tbs. butter (You can use olive oil instead. But, you know, sometimes it just has to be butter.)
  • 1 Tbs. soy sauce
  • Coarsely ground black pepper or Sansho (山椒)

Preheat the oven to 200°C / 400°F.

Put the potatoes in a pan with water to cover; add salt (the water should taste almost as salty as sea water). Bring to a boil and cook for about 5 minutes. (Do this while the oven is heating up.)

Drain the potatoes. Melt the butter in the same pan and add the soy sauce. Mix the potatoes and butter-soy sauce well, and put onto a baking sheet.

Roast for 25 to 30 minutes unti the potatoes are browned and cooked through. Serve warm or at room temperature sprinkled with a little sansho/sanshou pepper (available at Japanese grocery stores) or black pepper.

Want more butter + soy sauce?

Try corn on the cob with butter and soy sauce...delicious!

Filed under:  japanese potatoes summer produce

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Hi there, I have not thought butter and soya sauce will go well together. I will definitely try. I also now live in, Basel, Switzerland. I tried the very tiny ones once in Alsace, they were lovely. I have a small bottle of Sansho bought from 100Yen shop but do not really know what food will go well with it. Thx for the recipe. Thx Janet

Hmm... just soy sauce and butter huh? I guess living overseas too long just has me believe that potatoes can only be baked in herbs and olive oil(or butter of course!). Never really considered soy sauce, though when I used to bake chicken seasoned "Asian" style with soy sauce and sesame seeds etc, I used to always chuck some new potatoes in with them... Makes complete sense now! ^_^

Loving the new potatoes in season at the moment! Just had some the other day! Reading your post now has me craving more.

Maki, ever since I started reading your site I knew the time would come when I had to admit something to you. As a little girl growing up in the US I loved rice. I like it just about anyway it was cooked. But my all time favorite topping was soy sauce and butter! Ever since I've started reading Japanese food blogs I've felt so ashamed about that, LOL. This recipe made me feel a little bit better about loving the combination.

Don't be ashamed...butter and soy sauce (especially if a bit caramelized) is a magical combination!

I've used shouyu-bataa on ramen before, but this is an interesting new idea! I'll have to try it out! :)

OK. I found your site today, RSS'd it and then found this potato recipe. I live in Downtown Los Angeles, near Little Tokyo, and I walked to the Japanese super market and picked up some various flavors to cook with the potatoes.

FANTASTIC flavor. I really loved this potato recipe. I am not a baked potato fan but my partner is. I had one unintentional alteration and that was because I didn't have butter on hand... well I did but it was homemade honey-butter so I used it, which I think sweetened the recipe. I salted the water as described and even threw in some black sesame for fun.

Good. Good. Good. Yum-yum good.

Thank you so much for posting your recipe's. I live to cook, it made a great dinner.

Ooo, this looks delicious Maki! ^^ Thanks for the recipe, I'll try it soon :) Are there any more Japanese dishes with the soy sauce and butter combo? Haha, just wondering x)

i thoght i have to try these and i made them yesterday they where sooo delicious, they just melted on the tounge! there is no better potatodsh i think!

@ janet

thank's for the tipp with the 100yen shop. i'm from basel too :-)

@ maki
thank's for the recipe

I made these the other day and they were delicious! And very simple to make. Thanks for the recipe. I will make them again!

nice recipe, i'll sure try it. thanks for sharing.

We would like to feature this recipe on our blog. Please email if interested. Thanks :)


I made this recipe today and i really enjoyed. I couldn't find new potatoes so i used some organic fingerling potatoes.

This was really delicious! I've been looking for recipes to use up the over abundance of new pototoes I've found myself with (who knew it was so hard to eat an entire bag to yourself?) and this is one of the most delicious by far! Can't wait to try shouyu bataa corn-on-the-cob! ^^

Being half Japanese, half Irish, this should have been obvious to me. I tried this tonight as a side dish tonight. It was easily one of the best potato dishes I've ever had. Thanks so much.

estas patatas estan deliciosas mi bebe adia las papatas pero estas realmente le facinaron mmmmmmmmmmmmmm rikisimas ahora mismo hare mas

I was curious what the purpose is of boiling the potatoes
prior to roasting them?

I'm making them right now. I'll let you know how they turn out. I added a smashed clove of garlic into the butter & soy, then removed it prior to roasting. I plan on garnishing the potatoes with fresh chives & serving with Wasabi Flank Steak.