Spread apple slices in a wide dish of suitable size.
Combine rest of the ingredients except margarine in a mixing bowl to form crumbs mixture.
Sprinkle the mixture over apples and pour the melted margarine on all over the dish evenly.
Place the dish in preheated oven for just 4-5 min at 400 degrees F until apple becomes soft and juicy.
After that cool the apple crunch at room temperature them top with some whipped cream and cinnamon powder and chill for 15 min before serving.