How to Make It
Preheat the oven to 325°. Butter 6 large or 12 regular-size muffin cups. Line the bottoms with wax paper and brush with butter. Spread the pecans on a baking sheet and toast for about 8 minutes, or until fragrant. Transfer to a plate and let cool.
In a bowl, sift together the flour, baking soda, cardamom and salt. In another bowl, beat the butter until creamy. Add the granulated sugar and beat until light and fluffy. Beat in the egg and yogurt. Stir in the dry ingredients until fully incorporated. Fold in the apples and pecans.
Spoon the batter into the muffin cups and bake for about 40 minutes for large cakes and 30 minutes for regular cakes, or until the apples are tender and a toothpick inserted into the center of the cakes comes out clean. Let the cakes cool in the pan for 5 minutes. Invert onto a rack, remove the wax paper, then turn right side up and let cool completely. Dust with confectioners' sugar before serving.