Soak the beans for 12 hours. Then drain, wash, and dry them.
Heat the olive oil in the pot. Add the onions, carrots, celery, cayenne pepper, crushed tomato, tomato paste, a pinch of salt and pepper. Mix well and cook for about 4 minutes.
Add the beans to the pot and enough water to cover them.
Cover the pot and bring to HIGH pressure over medium-high heat. Stabilize and cook for 8 minutes.
After 8 minutes, release the pressure and open the cooker. Salt to taste, garnish with parsley if desired, and serve.