Preheat the oven to 350 degrees F (175 degrees C). Line cookie sheets with parchment paper.

Mash bananas in a large bowl. Add oats, raisins, yogurt, and cinnamon. Mix well and allow to sit for 15 minutes.

Drop spoonfuls of dough 2 inches apart onto the prepared cookie sheets.

Bake in the preheated oven until lightly browned, about 20 minutes.