In addition to providing protein and fiber, lentils are a significant source of folic acid. Even more folic acid comes from the wheat germ used to bind the burgers, and from the whole wheat buns. These burgers pack 143 micrograms of folic acid--more than one-quarter of a day's recommendation. Tzatziki, the garlicky Greek yogurt sauce, makes a healthful and tasty alternative to mayonnaise.
2 tomatoes, cut into 1/4-inch-thick slices (about 3/4 pound)
How to Make It
To prepare tzatziki, place cucumber on paper towels, and squeeze until barely moist. Place in a medium bowl. Spoon yogurt onto several layers of heavy-duty paper towels; spread to 1/2-inch thickness. Cover with additional paper towels, and let stand for 5 minutes. Scrape into bowl using a rubber spatula. Add the salt, crushed garlic, green onions, and extra-virgin olive oil; chill.
To prepare patties, heat 2 teaspoons oil in a medium saucepan over medium-high heat. Add onion; sauté 2 minutes or until tender. Stir in oregano, red pepper, and garlic; cook for 30 seconds, stirring constantly. Stir in broth, lentils, and sun-dried tomatoes; bring to a boil. Cover, reduce heat, and simmer 35 minutes or until lentils are tender; drain. Cool.
Place lentil mixture, cheese, and the next 6 ingredients (cheese through black pepper) in a food processor; pulse until coarsely ground. Divide lentil mixture into 8 equal portions, shaping each into a 1/2-inch-thick patty.
Heat a large nonstick skillet coated with cooking spray over medium-high heat. Add patties, and cook for 3 minutes. Turn patties over, and cook over medium heat 3 minutes. Spread 1 tablespoon tzatziki evenly on each bun top and bottom. Arrange the arugula, patties, and tomato slices over bottom halves of buns; top with remaining bun halves.
Note: You can freeze any uncooked lentil patties for up to 1 month: Separate the patties with wax paper, place in a heavy-duty zip-top plastic bag, remove excess air, seal, and freeze. Thaw in refrigerator before cooking.