To make the caramelized onions melt 2 tablespoons of butter in a skillet over medium heat. Add the onions and the salt and saute for 20 minutes or until the onions are a caramel color. Cool.

Preheat the oven to 200 degrees.

Gently stir together the yeast and warm water (water should be 100 to 110 degrees) until the yeast is dissolved.

Add the warmed potatoes, caramelized onions, sugar, and butter to the yeast mixture. Beat with an electric mixer until well blended. Add in flour one cup at a time, until the dough becomes more stiff and harder to beat, about 2- 2.5 cups. Turn the dough out onto a well floured surface and knead in the remaining flour. Knead for approximately 5-7 minutes, until the dough becomes smooth and elastic, sprinkling with flour as needed to prevent sticking.

Shape the dough into a ball and place in lightly greased oven safe bowl, turning once to grease the top as well.

Turn off the oven, cover the bowl with plastic wrap and allow to rise in the oven for 30 minutes or doubled in size.

Punch the dough down and turn it out onto a lightly floured surface. Divide the dough into 12 equal portions. With floured hands, shape each portion into a ball.

Place the shaped buns onto a parchment lined baking sheet. Preheat the oven to 350 degrees.

Cover again with plastic wrap and allow to rise again in a draft free space for 15-20 minutes, or until doubled in size.

Very gently brush each roll with the beaten egg wash and sprinkle with poppy seeds.

Bake the buns at 350 degrees for 15-18 minutes or until the buns are golden brown.

Cool on wire racks.