Preheat oven to 350 degrees. Butter one 9 x 13 or two 8 x 8 cake pans.
Cream together butter and maple syrup. Add eggs and applesauce and beat until well combined.
In a separate bowl, sift together flour, baking soda, baking powder, salt and spices. Ad the dry ingredients to the wet in three batches, thoroughly combining after each addition.
Fold in raisins and nuts if you are using them (I never do, but it's a nice option if you want a sturdier cake).
Pour into prepared pan(s).
For smaller pans, bake just 30 minutes. If using a single, larger pan, bake for 45-50 minutes.
Combine butter and cream cheese in a medium bowl and beat with a hand mixer. Add powdered sugar and vanilla extract and beat to incorporate. I prefer a very lightly sweetened frosting, so I use just 1/4 cup powdered sugar in this frosting. For a more assertive sweetness, use 1/2 cup (or more!).
Spread evenly on top of the cooled cake.