Preheat oven to 350° F. Oil or butter then flour baking pans, either 12 small loaf pans or two 9-inch cake pans.
Toss diced apples with lemon zest and lemon juice in small bowl; set aside.
In large bowl, combine melted butter, brown sugar and granulated sugar, beating well by hand or using an electric mixer. Add vanilla extract; beat in eggs, one at a time.
Stir together flour, baking soda, baking powder and salt in separate bowl. Fold flour mixture into butter mixture; batter will be stiff. Fold in apple mixture.
Pour batter into prepared pans and bake (small loaves 25 to 30 minutes, cake pans 45 to 50 minutes), until cake is golden and knife inserted in center comes out clean. Serve warm or at room temperature. Dust cooled cakes with confectioners' sugar or serve with freshly whipped cream.Makes 4 Source: