Cook potatoes
1. Place potatoes in a medium saucepan and cover them with cold water. Bring water to a boil, then reduce heat to medium and cook potatoes until tender, 20-30 minutes. Drain, reserving 1½ cups of the cooking liquid. While potatoes are cooking, bring milk to a simmer in a small pan, then remove from heat.
2. Mash the hot potatoes, then add the sugar, salt, and butter and blend well. Then add the reserved potato water and the milk and beat well. Cool mixture until lukewarm.
3. Add the yeast to ¼ cup warm water, stir, and set aside for five minutes until bubbly. Gradually add four cups of flour to the potato mixture and beat well.
Then add the dissolved yeast and blend well. Add the remaining flour, about ½ cup at a time, beating well after each addition, until the dough is stiff enough to knead. You may not need to use all of the flour.
4. Turn dough out onto a floured board and knead until smooth and elastic (about 5 minutes), adding additional flour if necessary. Brush a large bowl with a thin layer of oil and place the dough in the bowl. Turn dough to coat with oil, cover with a tea towel, and let rise in a warm location for about 2 hours, or until doubled in size.
5. Preheat the oven to 400°F. Lightly grease two rimmed baking sheets. Turn the dough out onto a floured board, gently punch it down, then roll or pat to a ¾-inch thickness. Pinch off pieces of the dough and roll them into balls, then flatten these slightly. You should make about 24 rolls. To end up with the right number, I used a knife to cut the dough in half, then in quarters, then made six rolls out of each quarter section. (Alternatively, you could cut out rounds using a biscuit cutter.) Place rolls slightly apart on the baking sheets, then let rise until doubled in size, approximately 45 minutes. Bake about 20 minutes, until golden brown on top. Serve warm.
