Preheat oven to 170 degrees C. Grease and flour a ring tin. Mix together the flour, baking powder and salt. Set aside.
In a large bowl, cream together the 90g 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 centre of the cake comes out clean. Let cool in tin for 10 minutes then turn out onto a wire rack and cool completely.
Hot Butter Sauce
In a saucepan, combine 230g butter, 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.