Preheat the oven to 350°. Line a baking sheet with parchment paper.
In a bowl, soak the raisins in hot water for 10 minutes. Drain and pat dry before adding them to the batter.
Beat the butter and sugar together until well mixed. Add in the egg and vanilla and mix until well combined.
In a medium sized bowl, whisk the flour, oats, baking soda, salt, cinnamon and ginger together.
Add the dry ingredients to the wet ingredients and mix until just combined. Mix in the raisins.
Scoop out the cookie dough into 1.5 tbsp balls. Place them 2" apart on a cookie sheet. Bake for 10-12 minutes.
Let the cookies cool for 5 minutes before transfering to a wire rack to cool completely.