Preheat oven to 350 degrees F. Line a baking sheet with parchment paper.
In a medium bowl, add peanut butter and egg and mix together well. Add oats and raisins and incorporate well.
Place 1-inch balls or rounded teaspoons onto baking sheet. Flatten slightly with spoon or make crisscross design with a fork.
Bake 10 to 12 minutes.
Allow to cool before eating.