Black bean burgers with chipotle ketchup

Ingredients

• 1 1/4 cups dried black beans, sorted, rinsed, soaked overnight and drained
• 3 cups water
• 1 bay leaf
• 2 plum (Roma) tomatoes, peeled and seeded, then diced
• 1 yellow onion, chopped
• 4 cloves garlic, minced
• 1 tablespoon tomato paste
• 1 tablespoon wine vinegar
• 1 chipotle chile in adobo sauce, minced
• 1 3/4 teaspoons ground cumin
• 1/2 teaspoon salt
• 1 1/2 tablespoons canola oil
• 1/2 red bell pepper, seeded and chopped
• 1/2 cup cooked brown rice
• 1/4 cup chopped pecans
• 1 green onion, thinly sliced
• 1 egg, lightly beaten
• 3/4 cup whole-grain breadcrumbs
• 6 whole-grain hamburger buns
• 6 slices tomato
• 6 slices red onion
• 3 lettuce leaves, halved