Early prep: Add all the ingredients except for the anko and beaten egg to the bread maker, set to knead, and complete the first rise. Should take about an hour.
Divide into 10 portions (about 57 g each), roll into balls, and let sit for 15 minutes.
Use a rolling pin to stretch out the dough. Place a rounded piece of bean paste on each round of dough. Fold up towards the center, like folding a tea towel. Put the seams on the bottom and push down with your hand to flatten.
Place the dough on a cookie-lined baking pan and cover with a damp cloth. Allow to rise a second time in the oven at 40℃ for 30 minutes.
Begin heating your oven to 180℃. Use a brush to coat the dough with the beaten egg and bake in the oven at 180℃ for 15 minutes.
This is what the center looks like (using 30 g of anko).
Without the glaze: Bake in the oven at 180℃ for 15 to 18 minutes.
Story Behind this Recipe
I've been making these since I first tried Saint Marc Cafe's mugwort bread 10 years ago (though I've fiddled around with the quantities a bit).
I like bean paste, so I use around 30 to 40 g in each bun (if you use too much, it'll become difficult to wrap up). If you want a stronger fragrance and flavor of mugwort, reduce the quantity of anko to as much as 10 g.