In a small saucepan, melt butter and dissolve brown sugar.
Place thin apple rings into bottom of 2 (9-inch) non-stick round cake pans. Sprinkle in dried cranberries. Pour butter and sugar mixture over apples and cranberries.
With an electric mixer, cream butter and sugar together. Add eggs, one at a time, and combine well. In a bowl combine sifted flour, baking powder and salt. Add flour mixture slowly to egg mixture while beating continuously. Combine vanilla and buttermilk. Add buttermilk mixture to batter and beat until just combined.
Pour batter into cake pans over fruit mixture. Bake for 25 minutes or until skewer comes out clean. Let cakes rest in pans on racks to cool. Unmold onto a serving platter.