In a large bowl, combine the water and yeast and allow to sit for five minutes.
Add butter, sugar, and egg and stir until combined. Add flour and salt and stir thoroughly until it forms a wet shaggy dough.
Cover with a towel or plastic wrap and let rise until doubled, about 1 hour.
Dump out onto a floured surface and shape dough into a ball. Roll dough out to a rough 12x17 inch rectangle. No need to be exact.
Add filling and shape:
Brush dough with melted butter. Combine cinnamon and sugar together and sprinkle over the dough.
Starting at one long end, tightly roll dough into a long log. Use a sharp knife or unscented floss to cut off the ends so you have clean edges, then slice into 12 even rolls.
Place in a greased or parchment paper-lined lined 9x13-inch pan. Cover and let rise again.
Bake:
Preheat oven to 350°F. Bake cinnamon rolls until golden brown, about 30-35 minutes.
Let cool slightly or completely, per your preference.
Top with frosting:
Beat butter, powdered sugar, cream, vanilla and salt with an electric mixer until light and creamy, 3-4 minutes. Scrape the bowl down once or twice.
Spread frosting onto warm or cooled rolls and serve immediately. (Adding frosting while the cinnamon rolls are warm will cause it to melt and turn into a thick glaze, while adding frosting to cooled cinnamon rolls keeps the frosting light and fluffy.)
These cinnamon rolls are best the day they are baked but will keep in an airtight container at room temperature for a few days.
Video
Notes
NOTES:
Use "quick rise" or "instant" yeast to make these cinnamon rolls even more quick and easy.
To make ahead: Cover shaped rolls with plastic wrap and let rise in the fridge for up to about 12 hours. Take them out of the fridge about 1-2 hours before baking so they have time to come to room temperature and rise a little.