These doughnuts were inspired by an-doughnuts(red bean doughnuts) that I found in my local Japanese grocery store. The doughnuts that I purchased were a cake doughnut base with a chunkier red bean paste(called tsubu-an) in the middle, finished with granulated sugar around it. While I liked the concept of it, I felt like there was a lot of potential for these doughnuts to be made even better than what I had tasted – the original showed promise, but maybe a few things I would tweak here and there. The first was the dough – I love cake doughnuts, but I felt like it did eat a touch dryer than I would have liked. My solution to that? Use a mochi-based doughnut dough instead. Made from taking miso-infused mochi and mixing it with mochiko, baking powder, and some soy milk to form an entirely gluten-free and vegan dough, I can happily say that I’m obsessed with this mochi doughnut texture. For the filling, I went with koshi-an, which is a finer red bean paste, because I wanted it to be more similar to a jelly doughnut, and I found that the tsubu-an got dryer faster from being fried. For the sugar, I went with a roasted miso and kinako sugar, that is blended to be less granular and more fine and powdered sugar-like.
It’s important to make sure that you freeze the red bean filling beforehand, as red bean paste is super soft, and you’ll wind up with it squeezing out of the sides if you tried to just pipe it straight into the dough. It’s important to keep the filling completely surrounded, or it will burn in the fryer. Other things to keep in mind are the frying times – unlike most doughs, you don’t want to fry this one until completely golden brown. Mochi has a tendency to puff up a lot, and with a paste-type of filling, that could cause a giant mess. You literally just want to fry the dough until it becomes blonde, since the dough is vegan, and is made of half already-cooked mochi, you don’t need to fry it for long for it to be fully cooked. The usage of miso paste in the dough replaces the egg, but it also helps keep the dough from puffing up too much. I took a similar approach to making boba with using half cooked and half uncooked starch so that your doughnuts can hold together, but will not come out tasting dense. The end result is a crispy, crunchy doughnut dough with a nutty and smoky sugar, and a sweet bean filling.
For the dough:
1 cup mochiko, in two parts
2/3 cups soy milk, in two parts
1 tbsp miso paste
1 tspn baking powder
1 tspn vanilla extract
Red bean paste(I used koshi-an, which is the smooth paste)*
Divide your red bean paste into 2-tablespoon portions and transfer into either the refrigerator or freezer to harden for at least 20 minutes. Microwave half of the mochiko with half of the soy milk for 1 minute. Transfer the microwaved mochi mixture into a bowl and mix with the remaining mochiko, miso, baking powder, soy milk, and vanilla to form your dough. Roll out the dough on a surface that is dusted with either mochiko or cornstarch so that it forms a 1-inch thick log. Divide the dough into 12 pieces. Flatten a piece into a thin disk, and place into that disk your red bean paste. Press the sides together to seal the dough around the paste in an even layer.
In a pot, heat up 2 inches of canola oil to about 330 degrees F. Fry the doughnuts for about 2 minutes, or until completely golden brown. Drain on a towel and toss in the roasted miso sugar to finish. Serve right away so that they stay nice and crunchy!
For the roasted miso sugar:
2 tbsp miso paste
1 cup granulated sugar
2 tbsp kinako(toasted soy bean powder)*
Spread the miso paste in a thin layer onto a parchment-lined sheet tray. Bake at 350 degrees F for at least 5 minutes, or until almost completely black. Transfer into a blender and puree with sugar and optionally kinako powder. The end result should be a fine powder. When not using this to toss doughnuts in, mix 2 tbsp of it with 1 cup of milk and a 1 tspn of hojicha powder if you want milk tea!