With an electric mixer, beat together sugar and oil.
Add egg, milk, canned pumpkin and vanilla and blend well.
In a separate bowl, mix together the dry ingredients. Add the dry ingredients to the wet ingredients and mix, just until incorporated.
Drop batter by spoonfuls onto a greased cookie sheet. Bake at 375 degrees F for 10-12 minutes. Allow to cool before frosting.
For the frosting
In a medium saucepan, combine the butter, cream, brown sugar and salt, and cook over medium heat, stirring constantly, until the mixture comes to a boil.
Remove from the heat and stir in vanilla and 1 cup powdered sugar. Let the frosting cool to room temperature and then stir in enough additional powdered sugar to make a good frosting consistency (you may not use the whole extra cup.)