Whenever I feel adventurous, Food52 is the place that I turn to. Rarely the case that I can't find anything I am looking for--but today, a search on miso muffin/miso cake returned a blank page. I recall having miso cakes in a Japanese restaurant, and I can't believe that there isn't recipe (in English) available.
I stumbled across this recipe on a Taiwanese lady Cecillia's blog. Here is a link to her original recipe. http://www.cecillia.com.tw/2012/07/blog-post_6.html —MackAFish
miso paste (generally white miso paste is used in baking, but you can always explore other types of miso paste!)