Peel the pear, cut into quarters and remove the core. Cut each quarter into very thin slices.
Mix cottage cheese with sour cream until smooth. Add cinnamon or vanilla sugar if desired.
Brush each slice of bread with a thin layer of cottage cheese dressing.
Lay the pear slices on the cottage cheese, sprinkle with cinnamon and cover with a second piece of bread with cottage cheese dressing on the inside.