Heat oil in the cooker, then add onions and garlic cloves. Sauté until deep golden brown.
Remove from cooker and puree with tomatoes in blender or food processor until smooth.
Return to the cooker and add broth. Heat until boiling.
Close and lock the lid. Bring up to pressure, reduce heat, and cook on High pressure for 10 minutes or 18 on Low pressure.
Release pressure and remove the lid.
Add cilantro and salt to taste. Pour soup into bowls and garnish with cheese and tortilla chips. Serve with lime wedges, if desired.
Calories: 304kcalCarbohydrates: 5gProtein: 14gFat: 26gSaturated Fat: 11gCholesterol: 53mgSodium: 1469mgPotassium: 343mgFiber: 1gSugar: 1gVitamin A: 511IUVitamin C: 24mgCalcium: 390mgIron: 1mg