For instant pot: Add 1 can of beans and 1 cup of water to a blender. Blend on high until smooth. Next, set the Sauté button then cook bacon until crisp. Stir often. Set aside on paper towels and blot. Add onions, carrots, and celery to pot and sauté until soft, about 5 minutes. Mix in tomato paste then add pureed beans, beans, broth, Italian seasonings, red pepper flakes, and black pepper. Cook on high pressure 20 minutes. After 20 minutes, turn off and let the pressure release.
Place 2½ cups of soup in blender and puree to thicken, then add back to the soup.
To serve: Ladle 1½ cups into each bowl and top with a little crumbled bacon. Top with chives, if desired.
For Crock-pot: Add 1 can of beans and 1 cup of water to a blender. Blend on high until smooth. Sauté bacon in a nonstick pan until crisp. Set aside on paper towels. Blot.
To the same pan, keep bacon fat. Add onions, carrots, and celery to the pan and cook until soft, about 5 minutes. Transfer vegetables to crock-pot. Stir in tomato paste. Next, mix in pureed beans, canned beans, broth, Italian seasonings, red pepper flakes, and black pepper. Cover and cook on Low Heat 7-8 hours. or High Heat for 3-4 hours (depending on your crock-pot) Once cooked, place 2½ cups of soup in blender and puree to thicken, then add back to soup.
To serve: Ladle 1½ cups into each bowl and top with a little crumbled bacon. Top with chives, if desired.