Combine milk and sugar in a bowl, and put in microwave until the temp is reached (it's supposed to be lukewarm, not hot).
Sprinkle yeast over the surface, and let it sit for 5-10 minutes until foamy.
Tiny bubbles should begin to appear on the surface or around the edge of the container and it should start to smell yeasty).
Add the yeast mixture to the bowl of your stand mixer with the dough hook attached.
Add the flour, salt, eggs and butter and knead for 8-10 minutes. It should form a ball, and be relatively smooth.
Let sit in a warm place, until doubled in size (about an hour?). Punch down.
In a small bowl, combine brown sugar and cinnamon.
Roll dough into a 16x21-inch rectangle.
Spread dough with melted butter and sprinkle evenly with sugar/cinnamon mixture.
Sprinkle the diced apple over the top.
Roll up dough and cut into 12 rolls. I use (plain, unflavoured) dental floss to do this.
Place a piece of dental floss under the rolled dough, 1 inch from the end. Bring the floss up around the dough and cross it over the top, cutting through the dough and filling. Repeat at 1-inch intervals.
Place rolls in a lightly greased 9x13 inch baking pan. Cover and let rise until nearly doubled, about 30 minutes. Meanwhile, preheat oven to 400 degrees F (200 degrees C).
Bake rolls in preheated oven until golden brown, about 15-25 minutes.
While rolls are baking, beat together caramel sauce, powdered sugar, cream cheese, salt and milk.
Drizzle/spread frosting on warm rolls before serving.
Notes
I recommend using bread flour vs all purpose flour. The gluten content in bread flour is what makes these rolls super soft and fluffy.Room temperature eggs do best in this recipeWhat kind of apples to use?I use whatever I have but particularly like both gala and granny smith apples.Apple pie filling will work, but the filling tends to ooze so go easy!What does "warm but not hot mean"? It means about 110 degrees F. We don't want to kill the yeast, but we want the milk warm enough to activate it.Cutting the rollsUse a sharp serrated knife to cut the rolls for a clean edge (don’t press down and squish!The BEST way to slice cinnamon rolls is using dental floss. Place a piece of (plain, unflavored) dental floss under the rolled dough, 1 inch from the end. Bring the floss up around the dough and cross it over the top, cutting through the dough and filling. Repeat at 1-inch intervals.Bread Machine InstructionsPlace dough ingredients in the pan of the bread machine in the order recommended by the manufacturer. Select dough cycle; press Start. After the dough cycle is done, turn it out onto a lightly floured surface. Continue the recipe from the Filling Step