Sweet potato hamburger buns

Peel and cube the sweet potatoes; put in a saucepan of cold water with a generous pinch of salt, bring to a boil, then simmer on medium-low until very soft.

Drain very well, mash as fine as possible, and cool to room temperature or barely warm.

In a bowl whisk the yeast with some flour and warm water; cover 15 or 20 minutes until bubbly.

Add the sweet potato, honey, salt, the egg and melted butter, then about 75 or 80% of the flour.

Knead with the dough hook a couple of minutes, scrape down, and add flour only until the dough pulls away from the sides; knead a couple of minutes more to a soft, slightly sticky, somewhat elastic dough.

Shape into a smooth ball, return to the bowl with a drizzle of oil rubbed over, cover and rise in a warm spot such as the turned-off oven about two hours, until doubled.

Turn onto a lightly floured surface, press out the air into a rectangle, and cut with a pizza wheel into halves, quarters, then each quarter into quarters.

Form each piece into a ball by stretching the top under, finish with a cupped palm on a barely floured surface, then press flat.

Place on lined baking sheets about an inch apart; rise until doubled, about 45 minutes.

Preheat the oven to 400; brush with egg wash and sprinkle with sesame seeds.

Bake in the center of the oven at 400 for about 15 minutes; cool completely before opening.