In a medium bowl, whisk together sugar, brown sugar, flour, baking powder, cinnamon, salt & nutmeg.
Add oil, applesauce, vanilla & eggs – stirring until just combined.
Fold in carrots & raisins (if using)
Generously grease the bottom & sides of the slow cooker – or use slow cooker liners for easy release.
Pour the prepared cake batter into the cooker.
Cover the top of the cooker with a piece of foil & then place the lid on firmly.
Cook on low 90 minutes – 2 hours, checking with the toothpick test after 90 minutes. Mine was just slightly over 2 hours.
Unplug the cooker & remove the insert. Place the cake (still inside the insert) on a wire rack to cool for a minimum of 30 minutes.
If you used a liner for your cooker, gently pull up on the liner & remove the cake, placing on the wire rack.
If you did not use a liner, use a butter knife or offset spatula & scrape in between the cake & the insert to separate.
Place one hand on the top of the cake & use the other hand to carefully tip the insert upside down to remove the cake. (you will be holding the cake flat on one hand)
Set aside the insert & grab the wire rack & invert it onto the cake & flip it back to upright so that the cake is now resting by itself on the wire rack to continue cooling.
Allow the cake to cool at least 60-90 minutes before decorating.