• Soak, rinse and drain beans (instructions for quick soaking provided in the post).
• Press the saute button on the pressure cooker. Add the chopped bacon and cook stirring often until the bacon is crispy. Remove the bacon and place it on a plate lined with paper towels.  
• Remove the bacon grease leaving about 1 tablespoon in the pressure cooker. Add the carrots, celery and onions and saute for about 4 minutes or until the onions become translucent. Stir in the tomato paste, diced tomatoes, broth, bay leaves and drained beans. 
• Close and lock the lid. Cook on Manual for 15 minutes. Let the pressure release naturally. Stir in the chicken bouillon (if using) and season to taste with salt and pepper.
• At this point, you can add the crispy bacon back to the soup or just garnish each serving with some bacon. Turn the pressure cooker to warm if you want to keep the soup in the pot for a while. 

Slow Cooker Instructions

• Soak, rinse and drain beans (instructions for quick soaking provided in the post).
  
• Heat a skillet over medium-high heat. Add the chopped bacon and cook stirring often until the bacon is crispy. Remove the bacon and place it on a plate lined with paper towels.
• Remove the bacon grease leaving about 1 tablespoon in skillet. Add the carrots, celery and onions and saute for about 4 minutes or until the onions become translucent. Add the  tomato paste and cook for about 2 minutes.
• In a slow cooker place the cooked vegetables, diced tomatoes, broth, bay leaves and drained beans. Cook on low for 8 hours or on high for 4 - 5 hours.
• Season with bouillon (if using) and with salt and pepper to taste. At this point, you can add the crispy bacon back to the soup or just garnish each serving with some bacon.