Plum Cornmeal Cake

1 cup flour
1/3 cup whole wheat flour
¾ cup cornmeal
½ cup sugar
1 tsp baking soda
Scant 2 tsp baking powder
½ tsp salt
1 cup buttermilk
2 tsp vanilla extract
2 eggs
1/3 cup melted butter, cooled
1 ½ cups pitted and sliced plums, tossed with 1 T sugar
Preheat the oven to 375 degrees. Grease and flour an 8-inch square pan. Combine flours, cornmeal, sugar, baking soda, baking powder and salt. In another bowl, whisk buttermilk, extract and eggs. Add butter, then quickly add wet ingredients to first bowl and stir. Pour into pan, then top with plums. Bake about 40-45 minutes or until brown.