Dough: 3/4 cup (1.5 sticks) unsalted butter 1 cup milk 3/4 cup plus 1 tsp suggar 1.25 tsp salt 3 * 1/4 oz envelopes (7.5 tsp) dry yeast 1/2 cup warm water 5 large eggs approximately 9 cups plain flour Filling: 5 cups firmly packed brown suggar 1.25 cups unsalted butter 3 tbsp ground cinnamon Frosting 1/2 lb cream cheese, softened 1.4 cup whipping cream (approx) 1 tsp vanilla extract 3-4 cups sifted icing sugarFor the dough, heat the butter with the milk, 3/4 cup of the sugar, and the salt in a small saucepan until the butter is melted. Set aside to cool.
In a large mixing bowl, sprinkle the yeast over the warm water, add the remaing teaspoon sugar, stir, and set aside for 10 minutes, until the mixture is bubbly. Add the lukewarm milk mixture and the eggs and beat until well combined.
Add the flour a cup at a time, stirring and using enough flour to form a stiff dough. Turn out onto a floured board and knead until smooth and satiny, approx. 10 minutes. Place the dough in a very large buttered bowl, turn to butter the top, and allow to rise, covered loosely with a tea-towel, in a warm place until doubled in bulk (approximately one hour).
Punch the dough down again and roll out to a large rectangle, 60 x 90 centimetres.
Butter two 9- by 13-inch glass baking dishes. For the filling, beat together the brown sugar, butter, and cinnamon until well combined. Spread evenly over the suface of the dough. Roll up lengthwise and cut at five cm. intervals to make 12 rolls.
Place six rolls in each buttered dish. Cover loosely with a tea-towel and allow to rise until doubled in bulk (approximately one hour).
Preheat the oven to 180°C. Bake the rolls for about 20 to 30 minutes or until puffed and browned. Cool to room temberature on racks.
For the frosting, beat the cream cheese, cream, and vanilla until well combined. Add the icing sugar and beat until smooth and soft, not stiff. Frost the rolls and serve immediately.