I have translated a recipe for you.
In Japan the flour is called ‘Kyouriki’ or ‘strong flour’ and Hakuriki or ‘weak flour’. Toast bread, swiss bread etc is make with 100% strong flour, and snack breads like melon pan are made with a mixture . When baking in the US, I use bread flour for the strong flour and all-purpose for the weak flour. Strong flour has 12% protein, weak has 8%. The crunchy upper layer is called 'cookie'.
All ingredients should be room temp.
Maple Melon Pan
‘Strong flour‘ 200g
‘Weak flour‘ 50g
Baking powder 1/2 teaspoon
Skim Milk (powdered) 10g
Warm water 140cc
Dry yeast 4g
Maple Syrup 50g
‘Weak flour‘ 120g
Baking Powder 1/2 teaspoon
Skim milk 1 tablespoon
This recipe says you can mix the flour and baking powder together and then put in a home bakery using the dinner roll setting.
If you do it by hand, time-wise it will need a 25 minute first rising, then shaping it into 9-10 balls followed by 10 minutes bench time,then covering the dough with the cookie layer, followed by 20 minutes for the second rising in total. Cover with plastic wrap and a damp towel for rising and bench time.
During the first rising you make the Cookie layer, shape it into a cylinder or a pattie, wrap in plastic wrap and refrigerate.
After shaping ,when the bread dough is resting (10 minutes bench time) take the cookie layer out of the fridge, and cut in into rounds (or pie wedges if you’ve made it into a pattie) then quickly shape them into balls. On plastic wrap, flatten out the cookie layer ball, place a dough ball in the center and then use the wrap to bring the cookie layer up around the bread. If you don’t us wrap, you need to use a tool to get under the cookie layer to bring it up off the counter and around the bread. Roll in granulated sugar, score the tops and let it rise (second rising) for 20 minutes. Bake at 180-200C (if your oven runs hot, the lower temp) for 12 minutes.
Here’s a video so you can see the steps. She’s making them with a green tea cookie layer, but the steps are the same.http://www.youtube.com/watch?v=2OmW79fkXPs