Preheat oven to 325 degrees F (165 degrees C). Grease and flour a 10 inch Bundt pan. Mix together the flour, baking powder and salt. Set aside.
In a large bowl, cream together the 6 tablespoons butter and 2 cups sugar until light and fluffy. Beat in the flour mixture alternately with the evaporated milk. Stir in the cranberries. Pour batter into prepared pan.
Bake in the preheated oven for 50 to 60 minutes, or until a toothpick inserted into the center of the cake comes out clean. Let cool in pan for 10 minutes, then turn out onto a wire rack and cool completely.
To make the Hot Butter Sauce: In a saucepan, combine 1 cup butter, 2 cups sugar, and cream. Bring to a boil over medium heat, reduce heat and let simmer for 10 minutes. Remove from heat and stir in vanilla. Serve slices of cake generously covered with hot butter sauce.