Dissolve yeast in hot milk in large bowl (preferably of an electric mixer fitted with a dough hook). Let stand 10 minutes.
Add sugar, pumpkin puree, flour, salt, and spices for bread. Beat at medium speed until a soft dough forms, about 2 minutes, or knead for about 5 minutes. If needed, add additional flour to form a smooth and moist (but not sticky) dough, beating an additional 3 to 4 minutes. Add softened butter and mix until just combined.
Place dough in a buttered, medium sized bowl, turning the dough to coat. Cover and let rise in a warm, draft-free place until dough has doubled in size, 45 minutes to 1 hour.
Meanwhile, combine all ingredients for Spiced Sugar in a shallow bowl. Mix well.
After dough doubled in size, punch it down and transfer to a lightly floured surface.
Divide evenly into golf ball sized pieces (1%1⁄2 ounces each). Roll each piece into a ball.
Butter a 10-inch Bundt pan or ring shaped cake pan. Dip each ball of dough lightly into melted butter, then dip heavily in spiced sugar.
Place rolls evenly in prepared pan, stacking on top of one another. Pour any remaining butter over the rolls and sprinkle with a small amount of any remaining sugar mixture.
Cover and let rise in a warm, draft free place until doubled in size, 60-80 minutes.
Heat oven to 350° F. Bake bread until puffed and light golden brown, about 35 minutes. Cool 5 minutes in pan.
Invert onto a serving plate. Serve warm or at room temperature.
*Substitute granulated sugar with brown sugar for a more caramelized look and flavor.