Preheat grill to medium and spray with nonstick cooking spray.
Whisk eggs, pumpkin puree, cinnamon, and nutmeg until frothy.
Dip bread slices in mixture, coating both sides.
Grill for about 3 minutes on each side (until each is crisp and brown).
Serve with walnut immediately.
* Note to make it extra special serve with candied walnuts and fresh whipped cream.