1 teaspoon canola oil
1 small yellow onion, finely chopped
2 cloves garlic, minced
1 1/2 teaspoons cumin
1 teaspoon ground chipotle pepper (or other ground chile, to taste)
3/4 cup canned black beans, rinsed and drained
2 slices firm whole-wheat bread, torn into small pieces
2 Tablespoons tomato paste
3/4 pound 85% lean ground beef
2 Tablespoons chopped fresh cilantro
1/2 teaspoon salt
1/2 teaspoon freshly ground black pepper
4 whole-grain hamburger buns
Preheat a grill to medium-high or preheat a broiler.
Heat the oil in a small nonstick skillet over medium heat.
Add onions and sauté until just softened, about 3 minutes.
Add the garlic, cumin and chipotle and sauté until fragrant, about 1 minute longer.
Transfer to a dish to cool.
Meanwhile, in a medium bowl, combine the beans, bread and tomato paste.
Use a potato masher or fork to mash them into a rough paste.
Add the ground beef, cilantro, salt, pepper and the reserved onion mixture.
Mix thoroughly, then shape into four 3/4 -inch thick patties.
Grill the burgers on a well-oiled rack, or broil them until they register 160º F on an instant-read thermometer and there is no trace of pink inside, about 5 minutes per side.
Meanwhile, toast the buns on the edge of the grill or in a toaster.
Makes 4 servings.