Mix yeast, sugar, eggs, milk, butter and salt together in a large bowl, all at once.
Add 4 cups of all-purpose flour. Mix well with a spoon, cover bowl with plastic wrap and allow dough to rise 4-6 hours on counter or overnight in the refrigerator.
Do not knead the dough.
Roll out dough into a long, thin rectangle on a lightly floured surface.
Spread on softened butter.
Mix together brown sugar and cinnamon, and spread evenly over the dough.
Tightly roll into a jellyroll shape, starting at the long end of the dough.
Use a string or floss to cut dough into 1-inch pieces and place into a greased 9x13-inch baking pan (I placed 15 rolls in a 9x13-inch pan so the rolls were touching).
Cover and let raise an additional 30 minutes.
Preheat oven to 375 degrees F and bake for 20-25 minutes or until golden brown.
In a bowl, mix together frosting ingredients and spread over baked rolls.