Sprinkle breadcrumbs in well-buttered 8-inch (2 L) square baking dish. Using 2 tbsp (25 mL) of the butter, spread one side of each bread slice with butter; cut into quarters. Line dish with half of the bread, buttered side up.

In large skillet, melt remaining 2 tbsp (25 mL) butter over medium-high heat; sauté apples for 5 minutes. Sprinkle with 3 tbsp (45 mL) of the sugar; sauté apples for 3 to 5 minutes longer or until apples start to turn golden (do not let apples become mushy). Remove from heat.

In bowl, whisk eggs well; whisk in remaining sugar. Gradually whisk in hot milk, vanilla, cinnamon and salt; pour half over bread in dish. Evenly spread apple mixture over top. Cover with remaining bread and pour remaining egg mixture over top.

Place baking dish in larger shallow pan. Pour 1-inch (2.5 cm) boiling water into larger pan. Bake in 325°F (160°C) oven for about 45 minutes or until custard is almost set. Remove baking dish to wire rack. Brush apple jelly over top of pudding. Serve hot or warm. Sprinkle with icing sugar and serve with whipped cream.