Place the raisins in a bowl with hot water.  Allow to sit for 30 minutes before draining and using in the recipe.

In a large bowl, beat the butter and sugars until light and fluffy.  I did this by hand, but a hand or stand mixer will work too.  Stir in the flour, cinnamon, and baking soda until just combined.  Stir in the oats, egg, and vanilla.  Once the dough comes together, cover the bowl with plastic wrap and refrigerate at least 24 hours and up to 4 days.  You read that right – 4 days.  The longer the dough chills, the more complex the flavors will be.

When ready to bake the cookies, preheat the oven to 350 degrees F and line a baking sheet with parchment.  Dollop golf ball sized portions of cookie dough on the sheet, well spaced and bake about 15 minutes until golden brown and barely set in the center.  Serve warm or cool completely on the tray.  Repeat baking with the remaining dough.

Cookies may be stored in an airtight container at room temperature for up to 5 days or frozen, wrapped in parchment and foil and placed in a zipper bag for up to 3 months.  Thaw at room temperature about an hour.