Tangzhong Soft and Fluffy Buns

1. Make the TangZhong first: bring the 20g bread flour and 100g water to a boil, whisking until thickened. Set aside in the fridge overnight until the mixture completely chills.
2. The next day, using a stand mixer, combine all the basic dough ingredients (250g bread flour, 100g whole milk, 50g heavy cream, 3g yeast, 30g sugar) with the chilled TangZhong. Mix until fully incorporated.
3. Add the 20g butter and mix for another 10 minutes until the dough is smooth and elastic.
4. Let the dough sit for 1-2 hours, or until it has doubled in size.
5. Cut the dough into equal slices, about 45g each, and roll them into round shapes.
6. Let the shaped dough rise again until doubled in size.
7. Lightly dust with flour (shift some flour).
8. Bake at 350°F (175°C) for 25 minutes.