Preheat oven to 350°F. Grease and flour the pan or pans of your choice or line with parchment paper. For cupcakes, lightly grease 2 muffin tins or line with papers and coat the papers with nonstick spray.
Whisk together the flours, baking powder and baking soda in a medium bowl.
Cream together the butter, sugar and salt in a large mixing bowl with an electric mixer until light and fluffy. Add the eggs, one at a time, mixing well after each addition and stopping to scrape the sides and the bottom of the bowl once or twice. Add one third of the flour mixture, mixing until incorporated.
Whisk together the vanilla and yogurt in a separate bowl or cup and add half of this mixture to the large bowl, again beating until the mixture is very fluffy, and scraping the sides and bottom of bowl. With the mixer running on low speed, add another third of the flour mixture, the remaining yogurt mixture, then the remaining flour, mixing well after each addition and stopping once or twice to scrape the sides and bottom of bowl.
Pour the batter into the prepared pans. Bake the cake for the appropriate time for the size of pan. Remove from the oven and cool for 15 minutes before removing from the pan. Place the cake layers or cupcakes on a rack to cool completely before frosting.
Baking time - 25-27 min for layers or cupcakes, 30-34 min for sheet cake.
I used these cute Happy birthday cupcake liners for the muffin tins.