Soak the raisins in hot water and dark rum.
Cream butter and sugar until light and fluffy. Add egg and vanilla. Once incorporated, add flour, baking soda, and spices. Mix to combine.
Add oats and drained raisins, mix with a spatula. Form into discs (makes 8), and place in the freezer until the oven is ready.
Bake on 350F for 20-25min.
Psst: I like storing these in a large ziplock bag to keep them soft and chewy.