Prepare the Mashed Sweet Potato: Bake the sweet potato at 350F for 45 minutes or until soft enough to mash. Let cool, remove the skin and mash using cheese grater or potato masher. Transfer in a bowl lined with paper towel. Light press to remove excess water. Set aside to cool while you prepare the yeast.*** If Boiling the Sweet Potato: Peel the sweet potato and cut into small cubes. The smaller the cubes, the faster it will cook. Pour water in a pan and add cubed sweet potato. Boil until the sweet potato are cook through and really soft. Drain the water and transfer in a bowl. Mash the sweet potato using a fork, or potato masher, or potato ricer. Light press to remove excess water. You will have more moisture in this method, so squeeze it a little bit m ore to remove the water. Activate Yeast: Microwave the milk for 20- 25 seconds until lukewarm but NOT hot, aim for 110F. If you have a baking thermometer, use it as it is the best way to be sure of the temperature. Hot milk will kill the yeast and the bread will not rise properly. Transfer milk in bowl of stand mixer (Refer to discussion above for other Methods of making this) and add 1/2 tsp of the granulated sugar and stir. Add the yeast and let rest for 10 minutes until mixture is foamy. If the mixture did not become foamy, either the yeast is old or the milk is too hot. Do NOT proceed until corrected, otherwise you will end up with a tough dense bread
Add Wet Ingredients: Set the mixer with paddle attachment and mix in remaining sugar (3 tbsp), egg, mashed sweet potato on low-speed, just to mix every thing together.
Add Dry Ingredients: Add flour, salt and mix on low-speed until combined, then switch to a hook attachment. Allow mixture to knead on medium-low speed about 15 minutes until smooth and elastic. If the dough is too sticky add 1 tbsp of flour at a time until the dough comes together, the dough should be slightly sticky, smooth, soft and but not too dry. If too much flour is added, the rolls will be dense and heavy. A good measure of correct texture is a clean mixing bowl with slightly sticky bottom, a soft, smooth and elastic dough just like the photo below.
Shape: Take the dough out from the bowl and lightly push the dough down with the heel of the palm of your hands. Divide into 6 or 8 portions. I used a kitchen weighing scale to portion the dough, you can also just estimate it.*** Roll into a Twist Bun: If you want to make it look more attractive, shape each portion into a twist bun. First, roll into a rope of 8-inch length, then do a circular move to starting from the end of the rope, circle around and then tuck the other end under.*** Rolls into a Ball: If you want to keep it simple and easy, simply shape each portion into a ball, like dinner rolls. Arrange in Baking Pan: 7-inch Ceramic Dish: Line the ceramic rectangle dish with parchment paper. Arrange each portion side by side.
Rest Period: Cover and let rest in a warm place for another 60 minutes. Preheat oven to 350F during last 15 minutes of dough rising (or however long it took to re-heat your oven)
TIP: To help the dough rise faster, leave the covered dough OUTSIDE the pre-heated 350F oven. The top of the oven hot surface will give the dough the heat it needed to rise properly. Alternatively, you can also pre-heat the oven to 110F then turn it OFF and put the covered dough inside, just don’t forget to remove it when you pre-heat the oven later.
Dust with Icing Sugar: After 60 minutes, the buns will be fully puff-up ready for baking. Lightly dust the top with icing sugar or flour. I use this option if I do not want to crack an egg just to brush the top.*** Alternatively, you can also use egg wash. Brush top with egg wash ( 1 beaten egg + 1 tsp water). Egg wash helps in the browning and gives a nice glossy texture. Bake at 350F 7-inch Ceramic Dish/Loaf Pan: Baked in the lower rack for 15 – 18 minutes.
Cool: Remove from the pan and transfer in a cooling rack. Let cool at least a5 minutes
