Butter a 5-6 cup soufflé dish or bowl that fits loosely into the cooker.
In another bowl combine the bread, raisins, walnuts and orange zest. And in another bowl mix the brown sugar, salt, cinnamon, milk, eggs and vanilla.
Pour this mixture into the bread mixture and transfer to the buttered dish. Cover tightly with foil.
Pour the water into the cooker. Place the pudding mold in the cooker basket and lower into the cooker. Close and lock. Bring to pressure, lower heat and cook for 20 minutes at high pressure (or for 37 minutes at low pressure). Release pressure and keep the cooker closed for 20 minutes.
Remove the lid and take out the dessert bowl. Loosen the foil and cool. For more color, run under the broiler.
Sprinkle with cinnamon and serve warm with whipped cream.