In the bowl of stand mixer fitted with the paddle attachment, mix together sugar, yeast, and warm water. Let the yeast mixture sit for 5 minutes. It should get foamy.
Add in warm milk, vegetable oil, salt and 1 &1/2 cup of the flour to the yeast mixture. Mix on medium-high for about 2 minutes. Switch to the dough hook attachment and turn mixer onto low. Work in additional flour, ¼ cup at a time, until the dough come together and pulls away from sides of the bowl.
Let the mixer go to 8-10 minutes on low to knead the dough.
Oil a large bowl. Form dough into a ball and place into the oiled bowl, turning to coat. Cover bowl with a clean towel or plastic wrap and let rise for 1 hour. It should double in size.
Ones the dough has risen, punch out the dough on to slightly floured surface. Divide the dough into 8-10 equal sized balls. (I used my kitchen scale and measured the dough to divide it. I also made 8 rolls and they were a little big for normal sized hot dogs.)
Roll the dough balls into long rolls in your hands. You will want them to be about 4 and ½ inches long, then flatten each slightly with your palm.
If using topping, sprinkle baking sheet with poppy seeds and lightly roll each dough piece in poppy seeds.
Place the rolls on baking sheet so that they are equally spread out. Cover with towel and let rest for about 45 minutes.
When there is 15 minutes left to the dough resting, preheat the oven to 400 degrees.
Whisk together the egg and water in a small bowl to prepare egg wash. Brush the top of each roll with the egg wash and sprinkle each with poppy seeds (if using.)
Place the roll in the oven and bake the rolls for 20 minutes. The roll will be lightly golden brown when done. Remove from baking sheet and let cool on wire rack
When ready to serve rolls, slice lengthwise pulling the knife only ⅔ the way through, leaving other side closed. Store in airtight bag or container.
Recipe by 2 Sisters 2 Cities at https://www.2sisters2cities.com/2013/06/homemade-hot-dog-buns/