Mix the apple and bulgur in a bowl, then stir in the yogurt or fromage frais and half the milk. cover and set aside for 30 minutes or until the bulgur is softened and swollen. The grain should still have some bite, although it can be left uncovered in the refrigerator overnight. Stir well and add extra milk necessary to make the mixture creamy. The mixture can be sweetened with artificial sweetener if desired.