If you've heard about the Engine 2 Diet and want to try an Engine 2 approved recipe, here's a sample recipe to try. This is Rip Esselstyn's "Raise the Roof" sweet potato vegetarian lasagna. It's so good, he says, that he served it at his own wedding! It's also low in fat and cholesterol-free. Recipe courtesy of The Engine 2 Diet, by Rip Esselstyn. When I made this recipe, I only needed one box of lasagne noodles because the veggie mixture was so plentiful that I couldn't fit in another layer. The flavor is great, and I think you could use rotini noodles and bake it in a casserole dish for an easier preparation. (Leave the sweet potatoes in chunks if you do that.) Notice that the recipe doesn't call for any oil. If you use a non-stick wok, just add a little water to the bottom and it works just fine.