1. In a pressure cooker put beans, water & oil. Pressure cook for 30 minutes. Use Quick Release Method. Drain & rinse.
2. Microwave onions, carrots, & celery until onions are soft.
3. Put cooked vegetables into slow cooker.
4. Add tomato sauce, mustard, & molasses. Mix.
5. Add drained beans. Mix.
6. Put bean broth through degreasing cup, then add enough of this broth to barely cover mixture. Stir.
7. Slow cook on high 3-4 hours.