Use any color pepper you prefer, or substitute black beans or pinto beans for the lentils. This makes a great side dish or a vegetarian entree if vegetable broth is used. From "Living the G. I. Diet".
Bring the broth, rice, salt, and thyme to a boil in a saucepan. Reduce the heat to low, cover, and cook for 25 minutes, or until the liquid is absorbed.
Remove the pot from heat and sprinkle the carrot and zucchini on top. Cover and let vegetables steam in the pot's residual heat for 5 minutes. Scrape the rice mixture into a large bowl, add the parsley, and fluff with a fork.
Whisk together 1/2 cup of the tomato sauce, the egg, and the cheese in a small bowl. Pour the mixture over the rice and toss to combine. Add the lentils and toss again. Set the mixture aside.
Cut the top off each pepper and remove seeds and ribs. Trim the bottom of each pepper, if necessary, to make it sit flat. Set the peppers in an 8-inch square baking pan and pack the lentil-rice mixture into the cavities. Spread the remaining tomato sauce on top of the peppers. Pour the water into the dish around the peppers and cover with foil. Bake for 40 minutes, remove foil, then bake another 20 minutes until the peppers are tender.