In a large (stand-mixer) bowl, add hot water, yeast and sugar and stir to combine. Set aside until bubbly, about 5 minutes.
Meanwhile, in a small stove-pot, add milk, maple syrup, butter and rosemary and cook over medium-low heat until butter melts, about 4-5 minutes. (Do not let boil!)
Add in mashed sweet potato to milk mixture and stir. Add to yeast mixture.
Using the stand mixer, add in eggs to combine. Then slowly add in flour until combined. Add in more flour if necessary until dough is smooth. Dough should be slightly sticky but not stick to sides of bowl or hands.
Cover and place in warm spot to rise for 1 hour or until doubled.
Preheat oven to 350°F.
Make rolls out of the dough to form 18 small balls. Place on greased baking sheet or cast iron pan.
Bake at 350°F for 25-30 minutes or until lightly browned.
Brush with melted butter and top with sea salt and extra rosemary. Best served warm.