Found this while scouting recipes for the Food Friends and Fun Culinary Quest on Yuku. It comes together quickly and takes advantage of seasonal fresh plums which I love but you can also use other fresh fruits.
Heat oven to 350F/180C degrees. Lightly coat a 9-inch pan with butter and sprinkle with cake or bread crumbs.
In a large bowl or stand mixer, cream together butter and sugar until light and fluffy. Add the lemon zest and mix well. Beat in the eggs one at a time along with the vinegar and vanilla until well incorporated.
In a separate bowl, whisk together the flours and baking powder. Add to the butter mixture and combine at low speed until thoroughly mixed. Transfer to the prepared pan, smoothing down the top.
Arrange the plums, cut side down, in a decorative pattern on the surface of the batter. Pushing down lightly on the plums. Bake 35 minutes or until a toothpick tests clean. Remove to a wire rack and let cool 20 minutes. Unmold and serve dusted with confectioners' sugar, if desired.