Preheat oven to 350 degrees. Spray 1 (9-inch) cake pan with nonstick cooking spray; set aside.

In a large bowl, beat butter at medium speed with an electric mixer until creamy. Gradually add sugar, beating until fluffy. Add eggs, one at a time, beating well after each addition. Add vanilla.

In a medium bowl, combine cake flour, baking powder, and salt. Sift twice.

Add flour mixture alternately with buttermilk to butter mixture, beginning and ending with flour mixture. Fold in pecans.

In a small microwaveable bowl, combine reserved pineapple juice and dried cranberries. Cover with plastic wrap and heat on High (100 percent power) for 1 minute.

Pour melted butter into bottom of prepared pan. Sprinkle evenly with brown sugar. Arrange pineapple slices in a single layer over brown sugar. Place cranberries in the holes at the center of each pineapple slice. Pour batter over pineapple slices.

Bake for 40 to 45 minutes, or until a wooden pick inserted in the center comes out clean. Let cake cool for 10 minutes in pan. Remove from pan and serve warm.