I make this, except without the diced tomatoes. It's fabulous. I find that it makes about 2 hearty vegan main event servings. Also, I've substituted canned, drained, and very very well rinsed cannelli beans (white kidney beans) and navy beans (instead of red lentils) & it's wonderful. The olive oil is unnecessary. Also, I like to give it a twist of fresh lime juice and kick it up more than a few notches with chiles, etc. It's a FAST and FRESH recipe, open to improvisation.
"La Dolce Vegan" is a fabulous cookbook, incidentally.