Combine 1 teaspoon sugar, water, and yeast together in a large bowl. Allow the mixture to sit until slightly bubbly – about 5 minutes.
Add the butter, egg, buttermilk, salt, and 2 cups of the flour. Beat for 1 minute.
Add the remaining flour gradually, using just enough to make the dough come cleanly away from the side of the bowl.
Knead by machine (using a dough hook) for 5-6 minutes or by hand for 7-8 minutes. Dough should be very soft and elastic.
Generously grease or butter a large bowl. Place dough in bowl and turn to coat dough completely.
Cover and let rise until doubled – about 1 hour.
Preheat oven to 375 F. Grease (or us an oil-flour spray) a 9-inch by 13-inch baking pan.
Punch down dough and divide it into 12 equal pieces. Shape into smooth balls and place in prepared pan.
Cover and let rise until doubled – about 1 hour.
Optional: Dust with flour or brush with an egg wash. Details in notes.
Bake for 18-20 minutes, or until the tops of the rolls are golden brown.
Notes
To Make Dusted Dinner Rolls: Use a small fine-mesh sifter or tea strainer to sprinkle flour over the top of the rolls before baking.To Make Egg Wash Dinner Rolls: Brush the rolls lightly with an egg wash (1 egg and 1 tablespoon water, whisked together) before baking.