Combine carrots, potatoes, sugar, raisins, flour, baking soda, ground cinnamon, all spice, and ground cloves in a large mixing bowl.

Transfer mixture into a mold or 1 pound coffee can. Secure wax paper over the top and place the filled can in a large pot with 2 to 3 inches of water. Cover the pot and bring the water to a simmer.

Steam the cake for 2 hours. Serve warm.

To make the sweet butter sauce: Combine butter, cream, sugar, and vanilla in a medium-size pot. Heat until warmed through and sugar has dissolved. Spoon sauce over warm carrot pudding to serve.