Spray a 6-cup soufflé dish with cooking spray, set aside.
In a large bowl add eggs, sugar, whiskey, vanilla, cinnamon, and nutmeg; beat until well combined. Add milk and mix well. Add bread and raisins and toss until well mixed. Pour into the prepared soufflé dish; cover tightly with foil.
Add 1 ½ cups water to cooking pot and place trivet and steam basket inside. Carefully place the covered soufflé dish in the steam basket; close and lock the lid. Select PRESSURE COOK program Level 3 and Time 20 minutes.
Meanwhile, combine chocolate and cream in a microwave-safe bowl. Heat on HIGH for 2 minutes, stirring every 20 seconds until mixture is smooth. Set aside and keep warm.
Once the timer beeps 3 times to indicate the end of cooking, let pressure release naturally on its own (about 10 minutes).
Remove the soufflé dish from the cooking pot and serve pudding warm or at room temperature with the white chocolate sauce.