Pumpernickel and onion give these rolls a distinctly savory flavor. Serve them warm with salted butter or a slice of cheese. They're equally at home for sandwiches or in a bread basket.
For the dough: In a large bowl, combine the dried onions and water; let the mixture sit at room temperature for 30 minutes. Add the remaining dough ingredients and mix until combined.
Knead at low speed in your mixer for 6 minutes or by hand on a greased surface with greased hands for 8 minutes. The dough will be shiny and slightly sticky.
Cover the dough and let rise in a warm spot for 45 to 90 minutes, until almost doubled.
Transfer the dough to a lightly greased work surface and divide it into 16 pieces weighing about 50 grams each for dinner rolls, or 12 pieces weighing about 60 grams each for sandwich rolls. Shape into rounds or ovals, as desired.
For the topping: In a small bowl, whisk together the egg white, molasses, and water. Brush over the tops of the rolls and dip them in seeds (if using). Place the rolls on a parchment-lined baking sheet.
Cover with greased plastic and let rise for 30 minutes to 60 minutes, until almost doubled in size. While the rolls are rising, preheat the oven to 375°F.
When the rolls have risen, slash the tops and bake for 15 to 20 minutes, until the internal temperature reads 190°F when measured with a digital thermometer. Remove from the oven and serve warm.
Store rolls wrapped on the counter for up to 3 days, or freeze for longer storage.
