2 tablespoons olive oil
1 onion, chopped
1 carrot, chopped
4 garlic cloves, chopped
2 teaspoons ground cumin
1 to 2 teaspoons chopped jalapeño chile with seeds, divided
2 15- to 16-ounce cans black beans, undrained
1 15-ounce can petite diced tomatoes in juice
1 1/2 cups low-salt chicken broth
Sliced red onion
Heat oil in heavy large pot over medium-high heat. Add onion, carrot, and garlic; sauté until vegetables begin to soften, about 6 minutes. Mix in cumin and 1 teaspoon jalapeño. Add beans, tomatoes with juice, and broth; bring soup to boil. Reduce heat to medium, cover, and cook until carrots are tender, about 15 minutes. Transfer 3 cups of soup to blender and puree until smooth. Return puree to pot. Simmer soup until slightly thickened, about 15 minutes. Season to taste with salt, pepper, and remaining 1 teaspoon jalapeño, if desired.
Ladle soup into bowls. Pass red onion slices and sour cream separately.