Potato Burger Buns

Directions

1. Place potatoes in medium saucepan and add water to cover. Bring to boil then reduce to a simmer. Cook until potatoes are cooked through, about 8-10 minutes.
2. Drain potatoes, reserving 5 tablespoons of the potato water in a small bowl. Return potatoes to the saucepan and place over low heat. Cook, shaking pot occasionally, until any surface moisture has evaporated, about 1 minute. Remove from heat. Process potatoes through ricer or food mill, food processor or mash well with potato masher. Stir in butter until melted.
3. In the bowl of a stand mixer, whisk together the warm reserved potato water, yeast and sugar. Let sit until foamy, about 5 minutes. Add flour, mashed potatoes, one egg and salt and mix until combined. Knead with dough hook on low speed until dough is soft and slightly sticky, 8 to 10 minutes.
4. Shape dough into ball and place in lightly greased bowl. Cover tightly with plastic wrap and allow to rise at room temperature until almost doubled in volume, about 40-60 minutes.
5. Turn out dough onto a lightly floured surface. Evenly divide into 9 pieces, form into smooth rounds, cover with a clean damp towel, and allow to rest 15 minutes.
6. Line 2 baking sheets with parchment paper or silicone baking mats. Firmly press each ball of dough into a 3-1/2-inch disk, expelling large pockets of air. Arrange on prepared baking sheets. Cover loosely with clean damp towels and let rise at room temperature until almost doubled in size, 30-40 minutes.
7. While rolls rise, adjust oven racks to middle and upper-middle positions and preheat oven to 425 degrees.
8. Brush rolls with egg wash and sprinkle with sesame seeds, if using. Bake runtil deep golden brown, 15 to 18 minutes, rotating and switching baking sheets halfway through. Transfer sheets to wire racks to cool for 5 minutes then remove from baking sheets. Serve warm or at room temperature.