Preheat oven to 350 degrees F. Use a paring knife or apple corer to remove the stem and seeds from the apples, making a deep hole where the filling will go.
Combine the brown sugar, butter and cinnamon in a small bowl and mix well to combine. Add the nuts. Spoon mixture evenly into each of the apples.
Add 1/4 cup of water to a baking dish and place apples on top.
Bake for about 40-45 minutes, or until apples are tender when pierced with a fork. Remove from oven and allow to cool for a few minutes.
Spoon the sauce drippings from the pan over the apples. Serve with ice cream, if desired.
