Preheat the oven to 325°F. Lightly grease a 9-inch round cake pan.
In a medium bowl, whisk together the flours, baking soda, and salt; set aside.
In a large mixing bowl, mix together the butter, honey, molasses and eggs.
Stir in the reserved flour mixture, then the sour cream or yogurt,
Scrape the sides and bottom of the bowl to be sure everything is evenly moistened, then mix for one minute more.
Gently pour the batter into the prepared pan.
Bake for 50 to 55 minutes, until the edge of the cake pulls back from the edge of the pan.
Remove from the oven and place on a rack to cool for 15 minutes. A
fter 15 minutes, invert the cake onto a serving plate and allow it to cool before serving.