In a medium saucepan over medium-high heat, melt the butter. When the butter stops foaming, add the bread crumbs, 2 tablespoons of sugar, and the cinnamon; stir to coat the crumbs evenly with butter. Reduce heat to medium-low and cook, stirring frequently, until the crumbs are dark brown, crisp, and fragrant, 4 to 5 minutes. Cool the crumbs to room temperature.
When ready to serve, with an electric mixer (or a whisk), beat the cream until it begins to thicken and beaters leave a trail. Add the remaining 1 1/2 tablespoons of sugar and continue beating until the cream is thick, nearly doubled in volume, and forms medium-firm peaks. To assemble desserts, spoon about 1/4 cup of applesauce into each of 4 serving glasses, then about 3 tablespoons of the cinnamon crumbs over the applesauce, spreading the crumbs into an even layer. Spoon about 1/4 cup of the whipped cream over the crumbs, spreading the whipped cream into an even layer. Repeat the layering, using up the remaining ingredients, but in this order: crumbs, applesauce, then whipped cream. Sprinkle with hazelnuts, and serve at once.