Start by placing the raisins in a saucepan with one cup of water. Bring the mixture to a boil over medium heat and let it simmer for about 5 minutes to plump the raisins.

In a separate bowl, combine the granulated sugar, cornstarch, cinnamon, nutmeg, and lemon juice. Stir well to combine.

Once the raisins are plump, drain any excess water and mix them with the sugar mixture until everything is well coated.

Preheat your oven to 425°F (220°C). Roll out your pie crust and place it in a 9-inch pie dish. Pour the raisin mixture into the crust, spreading it evenly.

Dot the filling with small pieces of butter if desired.

If you prefer a double-crust pie, roll out another pie crust for the top. Cut a few slits to allow steam to escape. If you’re keeping it simple, lightly cover it with aluminum foil to prevent burning.

Place the pie in the oven and bake for 15 minutes at 425°F. Then reduce the temperature to 350°F (175°C) and continue baking for another 35-40 minutes, or until the crust is golden brown.

Once baked, let the pie cool on a wire rack for at least 30 minutes before slicing to allow the filling to set.