Preheat oven to 350º. Lightly coat a 9" cake pan with cooking spray. Whisk together the yogurt, eggs, sugar, oil, zest and vanilla in a large bowl until smooth. Add flour, baking powder and salt and whisk until dry ingredients are just incorporated. Pour batter into prepared pan and smooth top. Bake until golden brown and a wooden pick inserted in center comes out clean, 35-40 minutes. Run a knife around the edge of the pan to loosen; invert cake onto a rack to cool completely, about 1 hour. Dust cake with powdered sugar and serve with fruit. Store cake at room temperature tightly covered.