Butter Mochi (バター餅)
Although it shares some similarities with the Hawaiian treat of the same name, Japanese Butter Mochi is a type of Wagashi (和菓子 – Japanese sweets) that’s a regional specialty of Akita Prefecture.
Traditionally, it was made by mixing pounded mochi rice with sugar and butter, but these days it’s more commonly made using mochiko, or glutinous rice flour. Soft and sticky, the sweet bites of buttery mochi make for a satisfying snack that delicious for both kids and grownups alike.
Because it’s so easy to prepare, this is also the perfect recipe to dive into the sweet world of Wagashi.
Why This Recipe Works?
- Using mochiko (mochi rice flour) is faster and easier than steaming mochi rice and then using mallets to pound it into mochi. Using a microwave to cook the mochi mixture is quicker and easier than cooking it on the stovetop.
- Using milk instead of water creates an ultra-creamy mochi that makes it taste like milk candy.
- Using cultured butter gives the mochi a more robust butter flavor.
Ingredients for Butter Mochi
- Mochiko – Mochiko is a flour made by milling short-grain glutinous rice or mochigomé into flour. By hydrating and cooking the rice flour, it turns into mochi. This allows you to bypass the usual process of soaking mochi rice in water and then steaming it before pounding the rice into mochi using large wooden mallets.
- Milk – Traditionally, the mochi rice used for this dish would be hydrated and steamed with water, but since we’re starting with Mochiko, it allows adding additional flavor by using milk as the liquid. For the most flavor, I recommend using either fresh whole fat milk or unsweetened evaporated milk.
- Sugar – I generally don’t use white sugar; however, it’s best to use granulated sugar for this dish. That’s because brown sugar will turn the mochi brown and adds a strong flavor that will overpower the flavor of the butter.
- Butter – As the name implies, butter is the primary flavoring of Butter Mochi. I recommend using cultured butter (a.k.a. European butter). Instead of churning fresh cream, this style of butter is fermented first, which increases the diacetyl content of the finished butter. This is the compound responsible for what we perceive as butter flavor, so the more diacetyl the butter contains, the more buttery your butter mochi will be.
- Potato starch – the starch keeps the mochi from sticking together once you’ve cut it. The trick here is to apply enough to prevent sticking but not so much that it makes the mochi chalky. If you think you’ve applied too much, you can use a pastry brush to brush off the excess. Other types of starch, such as cornstarch, will work as well.
- Other ingredients – Traditionally, butter mochi includes some egg yolk, which is added to give the mochi a yellow color. There is no flavor or texture benefit to adding egg yolk, and it tends to cook and clump up if you add it when the mochi is too hot, so I recommend leaving it out. You can also get creative and add other flavorings like vanilla extract or cocoa powder. These are delicious, but they cover up the taste of the butter, so I recommend trying this once without any other flavoring ingredients.
How to Make Butter Mochi
The first thing you’ll want to do is line a 5-inch square pan with parchment paper. If you don’t have a pan, you can just put the parchment paper on a flat tray or plate, but you won’t be able to cut the mochi into perfect squares.
Next, you want to add the mochiko and sugar to a large microwave-oven-safe bowl. You can then add about one-third of the milk and mix everything together to make a loose paste that is free of lumps. Then you can add the remaining milk and whisk it in.
Now you want to put the bowl into your microwave oven and set it at 600 watts for two and half minutes. If you cannot adjust the wattage setting of your microwave, find the wattage your unit operates at and adjust the time up or down accordingly (longer if it’s lower wattage, shorter if it’s higher wattage).
When it’s done, take the bowl out of the microwave. It will likely have a set layer at the bottom with liquid on top, and you want to mix everything together again. It’s okay if you have some small lumps, but just make sure you mixed the liquid back into the mixture. Now you want to add the butter and stir it in until it’s fully incorporated with the mochi mixture.
Put the bowl back into the microwave and set it for 600 watts and let it cook for three and half minutes this time.
The bowl will be very hot, so carefully remove it from the microwave and use a silicone spatula or wet wooden paddle to knead the mochi together. It’s going to be very hot and sticky, so be careful not to get the mochi on your hands.
It will start out crumbly, but as you mix it, it will get increasingly sticky. The mixture should also go from milky to translucent white. If this isn’t happening, try putting it back into the microwave oven at 600 watts for another minute or two.
Transfer your Butter Mochi into your prepared mold and then press it into the corners and flatten the top off.
Place this in your fridge until it’s cool and firmed up a bit. Then you can use a knife to cut it into bite-sized pieces. Once the mochi is cut, dust each piece with potato starch to prevent them from sticking together.
Other Japanese Sweets Recipes
Besides sharing a few ingredients in common, Japanese Butter Mochi is a different dish from the Hawaiian snack. The Hawaiian dish uses butter and mochi flour to make a batter that is then baked. It has a crust and the texture of a dense cake. Japanese Butter Mochi is mochi that has been flavored with butter and sugar and has a soft, chewy texture.
It was created in Akita Prefecture in northern Japan around 40 years ago as a high-energy snack for hunters. It’s since become a regional specialty of the area.
Butter Mochi is a four syllable name and is pronounced as follows:
ba like barb
ta- like tall
mo like motor
chi like cheek
No, this recipe is not plant-based. You could substitute in a plant-based milk and butter substitute like coconut oil, but part of the allure of this snack is the butter flavor. While it wouldn’t be “butter mochi” anymore, you could use the same ratio of ingredients and then add another flavoring like vanilla extract or cocoa powder to make a delicious mochi snack.
The butter and sugar content keeps the mochi from getting hard, so it can be refrigerated if you plan on keeping it for more than a day before eating it. I would still recommend letting it come up to room temperature before eating it.
sugar a little less than 1/2 cup
cultured unsalted butter 3 tablespoons
Potato starch for dusting
Prepare a 5-inch square mold by lining it with parchment paper.
Add the mochiko and sugar to a large microwave-safe bowl, and then add about 1/3 of the milk. Stir the mixture together until there are no lumps. Add the remaining milk and continue stirring until it is smooth.
Put the bowl in the microwave oven and set it to cook for 2:30 at 600 watts.
Remove the bowl from the microwave and stir the mixture together until it’s mostly smooth. It’s okay if you have some small lumps.
Add the butter and stir it into the mixture until the butter is fully melted and incorporated.
Microwave at 600 watts for another 3:30.
Carefully remove the bowl from the microwave oven and use a silicone spatula to knead the mochi together. The mochi is very hot, so be careful not to get it on your hands as you stir. The mixture should get very sticky and turn a translucent white color as you knead it. If this doesn’t happen, microwave it for another minute or two.
When you’re happy with the texture of your mochi, transfer it to the prepared parchment-lined mold and press the butter mochi into the corners and flatten off the top.
Chill the mochi in the refrigerator for a few hours to firm it up. When it’s cooled down, unmold the butter mochi and peel back the parchment paper. Use a sharp knife to cut it into bite-size pieces and then dust each piece with a generous coating of potato starch. Dust the excess starch off of each piece of mochi and serve.