Melt the butter.
Sift the dry ingredients (flour, baking soda, baking powder, salt) in a large bowl.
In another bowl, beat the eggs, sugar, butter, yogurt, and vanilla extract.
Add the wet ingredients to the dry ingredients, folding gently with a rubber spatula.
Gently mix in the fruit mixture, cardamom, and powdered vanilla.
The dough should be lumpy and just barely mixed.
Scoop dough into muffin cups and sprinkle with sugar.
Bake muffins at 375°F (190°C) for 15-18 minutes (until a knife inserted comes out clean).