Press the "Sauté" button; add celery, carrot, onion, bell pepper, dried parsley, bay leaf and 1/4 cup vegetable broth.
Sauté vegetables in broth until onions are translucent, about 8 minutes. If the inner pot becomes dry before onion is tender, add 2 tablespoons broth to prevent vegetables from sticking.
Add remaining broth, kidney beans, pasta, spinach, mushrooms, and pepper.
Continue to simmer soup until pasta is tender to the bite, 10 to 15 minutes, depending on pasta type.
Remove bay leaf. Press "Keep Warm/Cancel" twice to activate keep warm mode.
Serve right away or cover with lid, the soup is ready when your family is ready to eat. Enjoy!