My kids can't believe these cake-like buns are made with 1 potato

My kids can't believe these cake-like buns are made with 1 potato❗ 135g potato Chop the potato Move to a bowl 15ml water Cover and microwave for 4-5 minutes Mash the potato with a fork Move to a bigger bowl 150ml milk Mix well 25g white sugar 3g instant yeast 1 egg Mix well Save about 10ml for later 3g salt Mix well 250g bread flour Mix until ingredients are combined Cover and rest for 30 minutes 28g unsalted butter Microwave for 20-30 seconds After 30 minutes Add the remaining butter Knead the dough until the surface is smooth Cover and rise until double size Deflate the air bubbles Sprinkle some flour Place the dough on a kneading board Gently knead and shape the dough Leave a comment down below if you have a question! Cut the dough to the center Open up the dough Cut and divide the dough into 10 parts (or 12) Each piece is about 59g Take a piece of dough Shape the dough into a ba