In a large bowl, stir together the flour, baking powder, baking soda and salt.
In a separate bowl, cream together the butter and sugar until light and fluffy.
Beat in the eggs one at a time, then stir in the vanilla.
Mix in half of the sour cream or yogurt.
Fold in the strawberries.
Spread batter into prepared pan.
Bake for 40 to 45 minutes in the preheated oven. Cake is done when it springs back to the touch. Allow cake to cool in pan for at least 10 minutes before turning out onto a wire rack to cool completely.
Spread remaining sour cream or yogurt over cooled cake before serving.