Nutrition per serving may change if servings are adjusted.
3 tablespoons bulgur
¼ cup boiling water, plus 2 tablespoons water, divided
2 teaspoons extra-virgin olive oil
2 cups sliced onions
1 teaspoon sugar
1 teaspoon balsamic vinegar
¼ teaspoon salt, divided
8 ounces 92%-lean ground beef
1 tablespoon tomato paste, (see Tips for Two)
2 tablespoons chopped fresh parsley
¼ teaspoon freshly ground pepper
2 whole-wheat hamburger buns, split and toasted
Lettuce, for garnish
Combine bulgur and ¼ cup boiling water in a small bowl; let stand until most of the water is absorbed, 20 to 30 minutes.
Meanwhile, heat oil in a nonstick skillet over medium-low heat. Add onions and sugar; cook, stirring occasionally, until the onions are very tender and golden, about 15 minutes. Stir in 2 tablespoons water, vinegar and ⅛ teaspoon salt. Keep warm over very low heat, stirring occasionally.
Preheat the grill or broiler to high. Combine the bulgur, beef, tomato paste, parsley, the remaining ⅛ teaspoon salt and pepper in a medium bowl; knead thoroughly to combine. Shape into two ¾-inch-thick patties. Grill or broil on a lightly oiled rack until browned and cooked through, about 5 minutes per side. Place the patties on buns, top with the caramelized onions and garnish with lettuce.
Tips for Two: Transfer leftover tomato paste to an airtight container and refrigerate for up to 1 week or freeze for up to 3 months. Add to soups, chilis and sauces; stir into rice with oregano and cilantro to serve alongside Mexican dishes.