Warm the milk to about 100 °F. Whisk the milk, 2 tsp of sugar, and yeast together in a bowl. Cover and allow to sit until bubbling, at least 5 minutes.
Divide the butter into 4 pieces. After yeast mixture is foamy, beat in the remaining sugar and butter, until butter is broken up into small pieces.
Add the eggs and salt. Beat on medium speed until well combined.
On low speed, add the flour 1 cup at a time. After all flour has been incorporated, beat until the dough starts to pull away from the sides of the bowl.
Beat on low speed or knead by hand for an additional 3 minutes. If kneading by hand, do so on a floured surface.
Lightly grease a large bowl. Place the dough into the bowl and cover. Allow to rise for about 2 hours or until double in size.
Punch down the dough. Transfer to a lightly floured surface and roll into a large rectangle, about 12x18 inches.
Spread cinnamon filling evenly across dough and then top with apple filling.
Roll dough into a large 'log' shape. Using a very sharp knife, cut into about 12 rolls.
Place rolls into a greased 9x13 baking dish. Cover and let rise for about an hour.
Right before putting the rolls in the oven, warm the heavy cream and pour over top of the cinnamon buns.
Bake at 350 °F for about 25-28 minutes or until golden brown.
Let cinnamon rolls cool slightly and spread frosting over the top.