Mix the milk and sweetened condensed milk, and heat until about 40°C.
Combine half of the bread flour (100 g) and cake flour in a bowl, put the dry yeast in the middle, pour in the mixture from Step 1, and mix well until there are no lumps.
Add the remaining bread flour (100 g), salt, and butter brought to room temperature to the bowl, and knead until the dough comes together.
Once the dough comes together, transfer the dough to a working surface, and knead until a thin film of gluten forms (you should be able to see through the dough if you stretch it out thinly enough).
When done kneading, place the dough rolled into a ball in a bowl, spray with water, cover with plastic wrap, and let it rise at 40°C for an hour (for an hour in winter, and for about 40 minutes in summer).
Transfer the dough to a working surface, deflate the dough, and divide the dough into 9 equal portions. Roll them into balls and let it rest for 10 minutes.
Reshape the dough into balls (you could add fillings inside the dough ♪), and place in a square pan. After spraying water, place the whole pan (with the dough placed inside) in a plastic bag, and allow the dough to slowly rise in a warm location.
Note: I allowed the dough to rise slowly in a warm room for about 70 minutes. Allow the dough to rise until the tops have risen a bit above the rim of the pan.
Once the dough has risen 1.5-2 times larger than the previous size, bake in the oven preheated to 180°C for 12-15 minutes. After 7 minutes of baking time, cover with a sheet of aluminum foil.
Note 1: Since I didn't have a square pan, I used a heat-resistant glass dish (20 cm square, 5 cm deep) lined with parchment paper, and baked for 23 minutes.
Note 2: The speed of heat conduction will differ from a glass container to a baking pan, so if using a baking pan, please start checking the oven after 12 minutes of baking time.
I was able to get my hands on a square baking pan so I tried baking white bread with it. Please refer to "Helpful Hints" for baking time.
Story Behind this Recipe
I wanted to make really fluffy bread! And with this bread, my dream came true.
I wanted the bread to have a slight golden color on the tops, so I covered them with a sheet of aluminum foil after 10 minutes of baking time. But if you want to bake white bread, dust the tops with bread flour, bake at 180°C for 8 minutes, cover with aluminum foil, lower the temperature to 140°C and bake for another 7 minutes. In the summertime, preheat the oven to 180°C, lower the temperature to 140°C, and bake for 15 minutes (cover with aluminum foil if needed).