Add all ingredients to pressure cooker, reserving 1/4 cup tomato paste.
Set on MANUAL or PRESSURE COOK for 5 minutes.
Quick release and then stir in remaining 1/4 cup tomato paste. Serve with a selection of crackers, flatbread, pita bread, and olives. Caponata sauce can be served warm or cold, and you can also serve with pasta or couscou.