Lightly coat the bottom of a large sauce pan with cooking spray. Add the onion and celery to the pan and cook until tender. Stir in 3/4 teaspoon of the ground cumin, chili powder, and garlic. Stir in pepper, beans, tomatoes, and broth; bring to a boil. Cover and reduce the heat, then let simmer for 10 minutes.
Using an immersion blender, blend the soup in the pan. Blend until smooth.
Combine Greek yogurt, remaining 1/4 teaspoon cumin, cilantro, lime zest and juice in a small bowl. Drizzle over the top of the soup. Serve warm. Enjoy!