If you've heard about the Engine 2 Diet here's a sample recipe to try. This is Rip Esselstyn's "Raise the Roof" sweet potato vegetarian lasagna with tofu and plenty of healthy veggies. It's so good, diet creator Rip says, that he served it at his own wedding! It's also low in fat and cholesterol-free. This is a vegetable lasagna recipe packed full of broccoli, corn, mushrooms, carrots and more vegetable goodness.