In a large bowl, combine 2 1/2 cups of the flour, sugar, undissolved yeast and salt. In a saucepan, heat the sourcream, water and butter until warm (120°F). Stir the wet ingredients into the dry and stir in one egg. Add more flour, enough to make a soft dough and turn out onto a floured board where you will knead for 5-6 minutes.
Divide dough into 12 pieces and shape into balls. Place balls on greased cookie sheet and cover. Play sheet over a long, shallow pan, filled with boiling water. Leave this set up on your countertop for 20 minutes. Turn the oven on to 400 °F.
Take a pair of kitchen scissors and snip 4-6 cuts around the edges of the roll, you are trying to make it look like a flower! Beat the remaining egg and brush the tops of the rolls with egg and sprinkle with poppy or sesame seeds.
Bake the rolls for 12-15 minutes or until done (lightly browned). Remove from sheets and allow to cool on wire racks.