In a microwave-safe bowl, heat the milk in the microwave on high for 40 seconds. Check the temperature of the milk to see if it is between 110ºF to 120ºF. If not, microwave it at 10-second intervals until the milk is warm enough. If the milk is too hot, whisk the milk and let it cool for a few minutes. If you don’t have a thermometer, test the milk with your finger. The milk should feel very warm but not scalding hot.

Add 1 tablespoon of sugar to the milk. Then, add the yeast and stir to hydrate the yeast. Let it sit for several minutes while you prepare the other ingredients. The yeast should start to foam up after 1 or 2 minutes.

In the bowl of a stand mixer, combine the bread flour and salt. Add the melted butter, condensed milk, egg, and foamy milk/yeast mixture. 

Fit the mixer with the dough hook. Mix the dough on low until you don’t see any loose flour on the sides of the bowl. This should take 30 seconds to 1 minute. Then, increase the speed to medium-low and work the dough for 8 minutes. 

Scrape the dough out of the bowl onto a lightly floured surface and knead a few times. If the dough is feeling tacky, lightly dust your hands with flour. 

Shape the dough into a ball and place inside the greased mixing bowl. Cover the bowl with plastic (or a silicone lid) and let it rise in a warm place for about 1 hour, until the dough doubles in size. 

For the rest of the recipe, refer to the directions outlined in the tangzhong method.