This is from Cooking Light magazine, Jan/Feb 2009. It might be really good besides good for you, and no cholesterol.

Onions:
1 teaspoon canola oil
3 cups sliced onion
2 tablespoons balsamic vinegar
1 teaspoon sugar
1/8 teaspoon salt

Burgers:
2 1/2 cups (1/2-inch) peeled cubed sweet potato
Cooking spray
2 1/2 cups chopped onion
3 garlic cloves, chopped
1 cup regular rolled oats (oatmeal)
1 1/2 teaspoons ground cumin
3/4 teaspoon salt
1/4 teaspoon pepper
1/2 cup pecans, toasted and chopped
1 tablespoon canola oil, divided
6 Boston lettuce leaves
6 whole grain or whole wheat hamburger buns
6 tablespoons chili sauce

Onions: Heat 1 teaspoon oil in a large nonstick skillet over medium-high heat. Add the sliced onion to the pan and saute for 12 minutes, or until browned (not black), stirring occasionally. Stir in vinegar, sugar, and 1/8 teaspoon salt; cook 30 seconds or until vinegar is absorbed. Remove onions from the pan and keep warm. Wipe the pan dry with a paper towel.

Burgers: place the cubed sweet potato in a large saucepan, cover with water, and bring to a boil. Reduce the heat and simmer 15 minutes or until tender; drain. (I would use a lid if you can manage to keep it from boiling over.)

Heat that large nonstick skillet over medium-high heat and coat with cooking spray. Add the chopped onion and garlic to the pan; saute 5 minutes or until tender. Place the cooked potato, chopped onion/garlic, cumine 3/4 teaspoon salt, and pepper in a food processor and process until smooth; stir in the nuts. Divide the potato mixture into 6 equal portions, shaping each into a 1/2-inch patty.

Heat 1 1/2 teaspoons oil in the pan over medium-high heat. Add 3 patties to the pan and cook 4 minutes until browned. Carefully turn over and cook 3 more minutes until browned. Repeat the procedure with the remaining 1 1/2 teaspoons oil and 3 patties.

Serve on the buns topped with carmelized onions, the lettuce, and chili sauce or condiment of choice.

Calories: 376 per burger; Fat: 12.3 g Protein: 11.3 g Carb: 59 g Fiber 7.9 Gm Cholesterol: 0 gm Iron: 3.4 mg; Sodium: 785 mg; Calcium: 89 mg