Dredge the chicken in breadcrumbs. Heat 3 teaspoons oil in a large nonstick skillet over medium-high heat. Add the chicken; sauté 3 minutes on each side or until golden brown. Remove from pan.
Heat 2 teaspoons oil in pan over medium heat. Add fennel bulb, zucchini, and leek; cook 5 minutes, stirring occasionally. Add broth and next 6 ingredients (broth through tomatoes). Cover, reduce heat, and simmer 15 minutes or until the vegetables are tender, stirring occasionally.
Return the chicken to pan; cover and cook 12 minutes or until the chicken is done. Sprinkle with fennel fronds.