When I was growing up, we had a vegetarian potluck each week after church. The hosts of the meals were elderly ladies who had been vegetarian all of their lives. They made easy-to-prepare dishes with foods readily available at the grocery stores here in Nebraska. All of them lived into their nineties and most of them were able to remain independent up until the end. I have no doubt their diets were a major contributor to their longevity.
Each of the women had a cottage cheese loaf recipe she would bring from time to time. This is one I have adapted as my own.