In the bowl of a stand mixer, combine dry active yeast, warm milk, and 1 tablespoon of sugar. Whisk together and let stand for 5-7 minutes until mixture is foamy and yeast is fragrant.
Add remaining sugar, pumpkin puree, melted butter, and egg. Whisk to combine.
In a separate bowl, whisk together flour and sea salt. Set aside.
Attach dough hook attachment to stand mixer. With the mixer running on low speed, add half of flour mixture. Continue mixing on low speed. Add remaining half of flour mixture. Continue mixing. Scrape down bowl as needed to ensure thorough mixing.
Once dough has come together, increase speed to medium and knead dough for about 5 minutes until smooth. Dough will be a bit sticky and tacky. Do not add additional flour. Continue to knead until dough can easily be scraped off the sides of the bowl.
Transfer dough to a greased bowl. Cover with plastic wrap. Cover with dish towel and allow to rest at room temperature for 60 minutes until doubled in volume.
Place dough onto a lightly floured work surface. Dough will be slightly sticky. Lightly dust work surface and hands with flour as needed. Divide dough into 12 equal parts. Keep dough covered while you work. Roll into 12 balls and place on a parchment lined baking sheet. (9 x 13-inch pan)
Cover with plastic wrap and allow to rest and rise for another 45-60 minutes
Preheat oven to 350℉. Uncover dough. Brush tops of bread rolls with melted butter. Sprinkle poppy seeds on top. Bake for 25-28 minutes until bread has lightly browned on top and has an internal temperature of at least 190 degrees F. Allow to slightly cool in pan before dividing and serving.