Tang zhong has an unclear origin if you google it. It is basically a semi-cooked flour-water mixture that you add to the dough to make it moist as this thing retains moisture. For some detailed descriptions, see Dessert First Girl.
- 25 g bread flour
- 100 ml water
- Whisk flour and water together in a small saucepan. Place over medium-low heat on the stove.
- Cook, whisking constantly, until the mixture thickens into a pudding-like consistency and you can leave lines in the mixture, about 5 minutes. You might be tempted to walk away from the mixture at the beginning when it’s taking a while to thicken, but don’t – it will come together surprisingly quickly and you don’t want it to overcook.
- If you want, you can check the temperature – it’s finished when it reaches 65 degrees C (149 degrees F), but I don’t find it necessary.
- Let the tangzhong cool to room temperature before using. You can also store in the refrigerator for a couple days and bring to room temperature before using. If you see grayish spots in the tangzhong, discard it and make a fresh batch.
This is good for a bread using 350 g flour.