1 cup fat-free plain yogurt
3/4 cup sugar
2 eggs
2 teaspoons vanilla extract
2 cups all-purpose flour
2 teaspoons baking powder
1/2 teaspoon baking soda
1/2 teaspoon salt
1 1/2 cups chopped, peeled tart apples
3/4 cup chopped pecans
1/4 cup packed brown sugar
2 tablespoons butter
1 tablespoon fat-free milk