Preheat the oven to 350. Spray a standard size Bundt pan with nonstick cooking spray.
In a large bowl, whisk together the flour, cornmeal, baking powder, baking soda and salt.
In a small bowl, whisk together 1 cup yogurt, brown sugar, oil, eggs and orange juice until completely combined. Stir the wet ingredients into the dry just until incorporated. Pour into prepared the pan and bake until it is puffed and golden and a tester placed in the center comes out clean, 35 to 40 minutes. Remove from the oven, and when cool enough to handle, invert onto a wire cooling rack. Cool completely before slicing.
For the topping, stir together the remaining 1 cup yogurt, orange zest and powdered sugar. Slice the cake and serve with the yogurt topping drizzled over top.