nostr:npub16mznujsc4alkznqaqw7vtslucfvudjluwvkc2rg4aggy0k3ungeqemhm5n lentils, peas, whole grains you could soak (presuming one is not intolerant) like oats, barley, rice, or cornmeal/polenta? Broths can add a little depth depending on what you like and can tolerate. I will make a veg broth from mirepoix, and leave in some of the cooked mushy carrots and celery if I want a bit of tooth. 
I've found mushrooms can make a good broth as well, and don't really suffer from being cooked a long time (again if one is tolerant).