Sauté onion, leek and garlic in oil in large stockpot over medium heat, stirring frequently until translucent, about 10 minutes. Add rosemary and thyme. Cook 5 minutes longer.
Add broth, beans, salt, and pepper. Bring to a boil; reduce heat and simmer, covered,15-20 minutes.
Remove rosemary and thyme sprigs. Pour two-thirds of beans into blender or food processor. Cover; blend until pureed. Stir beans back into soup; heat through.