1. Lightly grease inside of 2 quart slow cooker.
2. Add oats, flax seeds, apples, raisins, vanilla, apple pie spice and maple syrup.
3. Pour pea or almond milk over oats, stir well to combine.
4. Cover and cook on low setting 4 hours.
5. Serve topped with walnuts and optional extra milk/sweetener if desired.