Combine both packets of yeast with warm water in a mixing bowl and stir to dissolve. This normally takes a few minutes and you can see the yeast change texture.
Add spice cake mix, grated carrot, flour, vanilla and salt after a few minutes. Use the dough hook to knead together the dough for a couple of minutes. Cover dough, place in a warm spot and let rise until doubled in size {about 30-45 minutes}.
Turn the dough out onto a floured surface and roll into a large rectangle {about 15″x12″}. Spread the softened butter over the dough. Sprinkle butter with brown sugar and cinnamon.
Spray a 9x13″ rectangle baking pan with non-stick spray. Starting with the wide section of the dough, that is the furthest from you. Begin to roll the dough into a tight circle toward yourself. When you get to the end, pinch to be sure that the end adheres to the rest of the roll. You should have a long roll. Cut the long roll in half using a serrated knife. Then take each half and cut 6 or 8 equal rolls.
Place the cinnamon rolls into the prepared pan {if you get more than 12, you might need another pan}. Cover rolls, place in a warm space and let them rise for 30 minutes in a warm place.
While the rolls are in their second rise, preheat the oven to 350°. Bake rolls for 25-30 minutes or until they are golden brown.
Remove from the oven and let roll them cool for 10 minutes.
While your carrot cake mix rolls are cooling, combine all of the cream cheese and butter in a bowl and mix until it is smooth. Add the vanilla and powdered sugar, continue to mix until you get a nice spreadable consistency. Spread on rolls and serve warm or store covered at room temperature for up to 5 days.